The United States, Japan, West Germany and four other major nations are quietly setting the stage for a new international accord to stabilize the dollar at rates modestly below levels that prevailed just before the stock market collapse two weeks ago, according to sources here and abroad.

If a new formal agreement can be brought off,it would signify to stock markets around the world that political leaders are giving first priority to lower interest rates to bolster economic growth, so as to put the world economy back on a recovery track.

But even if a new international meeting cannot be agreed upon -- or is delayed -- the Reagan administration, supported by the Federal Reserve System, has opted to try to stabilize the U.S. economy and stock markets by letting both interest rates and the dollar fall, at least temporarily.

Any successor agreement to the Louvre Accord -- the exchange rate stabilization policy adopted in Paris last February by the major economic powers -- is likely to be less rigid, using wide target ranges for the dollar against the yen and West German mark, with the understanding that changing conditions might require even more flexibility.

It would also be expected to reaffirm Japanese and West German willingness to push greater economic growth in their countries to counteract any economic slowdown caused by a reduction in the American budget deficit. And the foreign governments are hopeful that some assurance can be brought to the table that protectionist legislation can be sidetracked in Congress.

Officials would like to meet as soon as possible, but not until Congress and the administration agree on the specifics of a budget deficit reduction package.

Shigeru Tokunaga, a foreign exchange broker for the Fuji Bank in New York, said yesterday that the markets believe lower "target zones" for the dollar are already in use by the central banks in the major countries as they trade in currencies seeking to stabilize exchange rates. He said he believes that the new targets are around 130 to 145 yen to the dollar and 1.65 to 1.85 West German marks to the dollar.

The low dollar level of those ranges would represent a decline of about 15 percent against the yen and almost 10 percent against the mark since the Louvre Accord in February.

The Fed's easier-money policy -- designed to inject cash into the economy and lower interest rates -- has been formally announced by Chairman Alan Greenspan; the new dollar policy, not yet announced, is a natural derivative of the interest rate policy.

American officials now privately concede that efforts before the market's fall to keep the dollar from dropping below fairly narrow ranges against the yen and mark required a tight money policy by the Fed, which helped to raise interest rates, a factor that appears to have contributed to the stock collapse.

Officials acknowledge that a lower dollar -- making imported goods more expensive and providing a price "umbrella" for domestic manufacturers -- risks higher inflation. But after the collapse of world stock markets two weeks ago, even the conservative West German government appears to have decided that the global impact of U.S. inflation is a lesser evil than the global recession that might arise if markets continue to panic.

In a meeting with West German officials in Frankfurt on "Black Monday," Oct. 19, Treasury Secretary James A. Baker III made it plain that the only way the older, higher level of the dollar that prevailed at the time of the Louvre pact could be sustained would be through higher U.S. interest rates. The United States rejected that course.

Publicly, Baker said that higher interest rates here would bring economic disaster -- and statements by West German Finance Minister Gerhard Stoltenberg indicate agreement with Baker on that issue. Nonetheless, Stoltenberg is understood to have warned Baker that if the dollar is allowed to slide, pushing up the value of the mark, any improvement in West Germany's economic growth rate -- so urgently demanded by Baker -- will be inhibited because West German exports will be hurt.

Baker's response at the Frankfurt meeting was understood to have been along the line that a reversal of high interest rates in West Germany would encourage domestic expansion there, offsetting losses on the export side.

An overriding consideration that helps build support for a new international meeting on exchange rates and related issues is the desirability of preserving the coordination process painfully built up over the past two years. The seven cooperating countries -- known as the Group of Seven -- are the United States, West Germany, Japan, France, England, Canada and Italy.

Commenting on congressional testimony Thursday by Martin Feldstein, a former chairman of the Council of Economic Advisers who urged that the cooperative process that led to the Louvre Accord be scrapped, a West German official said: "Feldstein must be politically naive. That would be a prescription for disaster."

Officials have never revealed the Louvre targets -- or even that they exist. But the two critical "zones" -- to be defended by central bank intervention -- were said to be around 150 to 160 yen and 1.80 to 1.90 marks to the dollar. In April, the target for the yen was changed, focusing on 140 yen to the dollar. The actual prices in exchange markets remained close to 140 yen and 1.80 marks for much of the year until West German interest rates started to move up, just prior to Black Monday on Wall Street.

A European official familiar with Bonn government views, acknowledging that the Louvre rates can no longer be defended, said yesterday: "Between 1.70 and 1.80 {marks to the dollar}, they {the Germans} would survive -- they can digest that." Tokunaga said that in his opinion, despite the repeated complaints by the Japanese government over the negative effects of a higher yen, a range of 130 yen to 145 yen for the dollar is acceptable to Tokyo because "it can help cool down the Japanese economy."

One basic reason for restrained optimism on chances for a new G-7 meeting is the progress reportedly being made by the president and Congress toward negotiating a meaningful reduction of the budget deficit. If a "package" of deficit reduction measures is, in fact, agreed upon, it can be brought to a new meeting of the major powers as the linchpin of a new dollar accord.

"Without evidence that the president and Congress can make a bipartisan deal on the deficit that will have a long-term effect, there's nothing," said a European official.

He added that the West German government -- which has been sharply divided on how to meet the implications of a further decline in the dollar -- is "not really seeking a new G-7 meeting. But that doesn't mean the Germans would resist one, once the United States gets its act together. But the meeting would have to be well prepared, with a positive result assured."

A Reagan administration official, choosing words carefully, agreed, saying: "At this stage, we'd be out of our minds to get into a meeting without knowing exactly what we come out with."

British Chancellor of Exchequer Nigel Lawson said yesterday that another meeting of finance ministers and central bankers would be "sensible," but would be "wholly counterproductive and wholly damaging" without private agreement on the result beforehand.