TORONTO -- As French Canadians in Quebec move inexorably toward a referendum on political independence, an ambivalent English Canada appears to have given little consideration to the ultimate form -- and cost -- of sovereignty for the province.

Testimony at almost daily public hearings being held across Quebec by a joint legislative and private commission empaneled to consider the province's future has vaguely sketched out a variety of sovereignty options. They range from an outright unilateral declaration of independence to superficial changes in Canada's constitution that would result in limited autonomy for Quebec, keeping it in the 123-year-old confederation.

Between these extremes are a number of closely related proposals that seem to be favored by a majority of Quebeckers. They would drastically alter the political composition of Canada but leave Quebec with something less than the status of a nation-state totally independent of the nine predominantly English-speaking provinces.

But English-speaking Canada has shown little evidence of thinking through what shape the country may take. Opinion surveys show that many English Canadians have either accepted with indifference the notion that Quebec will separate or are terrified by the prospect of a breakup of the union. But in either case, the polls indicate that they have given little consideration to specific alternatives of a political restructuring of the country.

"In English Canada, there is a mixture of indifference and avoidance, even if there is an awareness that the problem is there and can't be escaped. So, it is very important that people, especially in the business community, know what the costs and benefits of separation are," Thomas P. D'Aquino, president of the Business Council on National Issues, said in an interview.

It is uncertain when Quebec might hold a referendum on sovereignty, although the province's governing Liberal Party has cast little doubt that there will be one. In 1980, at the height of power of Rene Levesque's separatist Parti Quebecois, a similar referendum was narrowly defeated in Quebec.

Gil Remillard, Quebec's minister for justice and intergovernmental affairs, said the current hearings into the province's future "will eventually have to be completed by a consultation of {Quebec's} people." Even some staunch federalists in Prime Minister Brian Mulroney's government acknowledge that a referendum on sovereignty is inevitable and that only the framing of its question and timing remain question marks.

The Belanger-Campeau Commission in Quebec will not begin detailed work on specific sovereignty options until next month, when it plans to call in a series of constitutional experts to evaluate the benefits and drawbacks of various constitutional models.

But out of the testimony presented to the commission so far, and from independent studies by academic and business groups, have emerged a number of blueprints of what a new Canada ultimately may look like. Constitutional experts say any new political status for Quebec is not considered likely until close to the end of the century, given the years that a negotiated constitutional revision might take.

One set of constitutional models currently under study was prepared by Ronald L. Watts, director of the Institute of Intergovernmental Relations at Toronto's Queen's University, for the Ottawa-based Business Council on National Issues.

The options outlined by Watts include:

Retention of the existing federal system, which Watts regards as an unlikely option given the polarization of Quebec and English Canada in the wake of the collapse last June of proposed constitutional reforms. These are known collectively as the Meech Lake Accord, which would have granted Quebec special status as a "distinct society" and redistributed powers shared by the federal and provincial governments.

A more decentralized federation that would devolve more powers, including some taxing authority, to Quebec and give the province control over many programs now run by the federal government.

A confederations of regions, in which four or five geographical areas would function autonomously under a central superstructure responsible for coordinating monetary, defense and other major policy concerns. The regions would likely be the Atlantic provinces, the Prairie provinces, Ontario, Quebec and, possibly, British Columbia.

A "bipolar" federation, consisting of Quebec and the rest of Canada. The major problem with such a system, Watts noted, would be that the three-to-one population ratio between the two federations would probably lead to intractable disputes over representation on a central authority.

A loose "sovereignty-association" confederation, which is advocated by many political moderates in Quebec and which formed the basis of the 1980 referendum. With Quebec as one unit and the remaining nine provinces as the other, this system would leave a central government responsible for a common market and shared armed forces. However, Watts said it is unlikely that the 75 percent English-speaking majority would accept a Quebec veto on major issues, and the arrangement would almost certainly lead to repeated deadlocks.

Complete independence for Quebec, which Watts pointed out would raise difficult questions about the allocation of Canada's assets and liabilities, boundary adjustments and other issues.

So far, Canadians appear to have paid little attention to the cost to both English Canada and Quebec if the confederation is dismantled and replaced with a radically different political structure.

"I don't think anyone has really thought this through on an accounting basis. The whole process is not being driven by economists with a detached viewpoint; it's being driven by politicians and special interest groups," said Patrick Grady, an Ottawa-based economist.

To begin with, Grady said, Quebec would have to be persuaded to share its portion of the $380 billion national debt, which, on a population ratio basis, would amount to $95 billion. If the province resisted, Ottawa could threaten to withhold repayment of its debt to individuals and institutions in Quebec, which could disrupt financial markets and the provincial economy at a time when Quebec would be most in need of economic stability to reassure nervous investment markets.

Economists pointed out that even a monetary union, which is advocated by virtually every proponent of Quebec sovereignty, would be difficult to arrange because English Canada, which is three times as large as Quebec, would be reluctant to share control over the central bank and monetary policy.

A number of witnesses at the Belanger-Campeau hearings have suggested that Quebec could link its own currency to the Canadian or U.S. dollar. Grady and other economists said this would gain international confidence in the stability of Quebec's currency but that such a linkage would mean that the province would relinquish an independent monetary policy.

Also, Grady said, under any Canada-Quebec free-trade agreement, there would probably have to be border control points and that the Canada-U.S. free-trade pact would not automatically apply to an independent Quebec.

In 1989, Ontario exported $16 billion worth of goods to Quebec and imported $13 billion from the French-speaking province, a trade flow equivalent to that of many medium-sized countries.