House Minority Leader Robert H. Michel (R-Ill.) indicated yesterday that President Reagan may have to settle for substantially less than the $16 billion in spending cuts and new revenues that he proposed in his latest economic proposal to Congress.

The administration would be doing "pretty well" to get $12 billion in new savings, and even a $10 billion cut would be pointing the budget "in the right direction," Michel told reporters.

"If we don't achieve the whole $16 billion, there's nothing sacrosanct about it," added Michel, who played a critical role in steering Reagan's initial $35 billion package of budget cuts through Congress last summer.

But even as Michel was saying the president might have to settle for less than he has asked, the president seemed to be gaining ground in his effort to scale back the huge departments of Labor and Health and Human Services appropriations bill that is headed for House floor action next week.

The $87.3 billion bill, which Republicans contend exceeds Reagan's new spending targets by $2 billion to $3 billion, will be the first to reach the floor of either house since Reagan announced last week that he wants to cut domestic appropriations by 12 percent in the 1982 fiscal year that started yesterday. As such, it has emerged as a new test of Reagan's crusade for budget cuts.

It had been targeted for floor action today but was postponed until next week, ostensibly for routine scheduling reasons. But, even as moderate northeast and midwest Republicans came out against anything like a 12 percent cut in the bill, prominent Democrats on the House Budget Committee came out in support of efforts to send the bill back to the Appropriations Committee for new surgery.

Claiming the bill exceeds congressional outlay targets by $763 million, Rep. Leon E. Panetta (D-Calif.) said he and House Budget Committee Chairman James R. Jones (D-Okla.), along with committee member Les Aspin (D-Wis.), would join Rep. Ralph Regula (R-Ohio), a member of the Budget and Appropriations committees, in urging the bill's recommittal.

Regula said he was considering calling for about $750 million in cuts, including reductions in funds for job training, health planning, bilingual education, the National Institutes of Health, the Bureau of Labor Statistics and departmental management expenses.

It would be the first time that Budget Committee Democrats moved against an appropriations bill this year. "If it were somewhat closer to the target , we'd probably leave it alone," Panetta said. "But this was so large we couldn't let it go by."

Panetta, who was the point man for House Democrats in the earlier round of budget cuts, said he believes the bill will probably be cut back in any case. "On a program-by-program basis, cuts would probably pass" on the House floor, he said.

While the northeast-midwest GOP "Gypsy Moths" caucused yesterday and came out against across-the-board cuts in the bill, Michel said Panetta's support, coupled with likely backing from conservative Democrats, would give the Republicans "a shot" at forcing substantial reductions in the measure, either through amendments or recommittal to the Appropriations Committee.

In any case, administration strategists expressed confidence that, in voting on a recommittal motion, the House would produce the 145 votes (one-third plus one) necessary to sustain a presidential veto. Reagan vowed again yesterday at his press conference to veto any spending bills that would "bust the budget."

Meanwhile, Reagan asked Congress to approve $737 million in deferrals of money that has already been appropriated, which were described as largely routine. Most of the savings, $596.6 million, would come from continuation of earlier deferrals. Among the new deferrals were about $135 million from coal conversion projects and about $50,000 from payments to survivors of the Tuskegee Institute's studies of syphilis.