A Federal Home Loan Bank Board bill to restructure thrift institutions has attracted broad support at the National Savings and Loan League meeting here, while an emergency assistance bill approved by the House Banking Committee has drawn little favor.

League officials are saying the bank board bill is their best vehicle for allowing S&Ls to compete with other financial institutions.

The legislation, proposed by FHLBB Chairman Richard T. Pratt, is considered the basis for survival of thrift institutions. It would virtually rewrite the Homeowners Act of 1933, giving S&Ls power to operate almost any type of business they choose.

Another, broader measure, introduced by Sen. Jake Garn (R-Utah), chairman of the Senate Banking Committee, would reshape the financial services industries.

Despite Garn's belief that his bill would eliminate serious problems faced by savings and loans associations, industry officials said today they prefer the Pratt bill, which Garn had introduced earlier.

"I think the Pratt bill is the best that could come down the pike," said Robert B. O'Brien Jr., chairman and president of Cartaret Savings and Loan Association of Newark.

Although O'Brien and others think the Garn bill has considerable merit, they prefer the Pratt measure because it would, in their opinion, allow S&Ls to compete on the same level as other institutions.

Indeed, several officials yesterday stressed the need to compete on a broader scale. Open competition, they claimed, is the best hope for the S&L industry's survival.

"Give us two years to get healthy and competition will seek its own level," said William E. Waldie, president of Dominion Federal Saving & Loan Association of McLean. Waldie said he welcomed broad-scale competition, something Dominion already is trying.

"We are supporting the Garn and Pratt legislation with some modifications," said Richard S. Lawton, president of the National League.

Lawton said the league does not support "the bare-bones regulators' bill" in the House because it doesn't provide much-needed asset powers.

The so-called regulators' bill, which would give agencies emergency powers to handle financially troubled or failing institutions, was introduced in the House by Banking Committee Chairman Fernand J. St Germain (D-R.I.).

Lawton said the Banking Committee wants to separate asset powers from the regulators' bill, but he said the two should be considered in a single package. He also said members of Congress want the thrift industry to be regulated fully while competing in a free-market economy.