The House Armed Services Committee has added a new twist to the effort to sell the country on the MX missile.

Rep. William L. Dickinson (Ala.), ranking Republican on the panel, has recommended to President Reagan that two Minuteman missiles be scrapped for every MX deployed in a Minuteman silo.

Such a "build-down," Dickinson said, would demonstrate that Reagan is pursuing arms control at the same time as he is modernizing the missile force by deploying the 10-warhead MX.

Dickinson said he tried out the idea on Reagan at the White House on Tuesday and that the president responded: "It sounds like the kind of thing I'm talking about."

Dickinson has added specificity and Republican political thrust to the idea of scrapping old nuclear weapons when new ones are deployed, a concept favored by such senators as William S. Cohen (R-Maine) and Sam Nunn (D-Ga.).

Along with the MX-for-Minuteman build-down, Dickinson and his allies are pressing for development of a small, single-warhead missile that would be carted back and forth on U.S. military bases to make it hard for the Soviets to target or hit. Dickinson said an anti-ballistic missile could be added if necessary to protect the MX missiles standing in existing Minuteman silos.

Acknowledging in an interview that he was trying to put together a something-for-everybody package, Dickinson said, "I'm trying to get something politically palatable that meets our defense needs."

The MX-for-Minuteman scheme is expected to be discussed today when some House Democrats meet with Brent Scowcroft, chairman of Reagan's MX panel, and several of its members to discuss the latest basing schemes for the homeless missile.

Rep. Les Aspin (D-Wis.), co-chairman of the defense panel of the House Democratic Caucus, which is holding the luncheon, said a growing number of lawmakers and administration officials recognize that getting the MX deployed is a political problem, not a technical one. Aspin said they are trying to build a consensus for the MX the same way Reagan's Social Security panel built a consensus for revising that system.

Aspin said he could go along with producing the MX but said he favors eventually producing small, mobile, single-warhead missiles and negotiating silo-busting missiles such as the MX and the Soviets' SS18 out of existence.

He said these missiles, with their ability to destroy a missile before it can be launched, increase the temptation to fire first and thus destabilize the balance of terror between the superpowers.

Dickinson said he and Anthony R. Battista of the House Armed Services Committee staff drafted the MX-for-Minuteman proposal in hopes of avoiding a repeat of last year's congressional refusal to fund MX production.

Rep. Thomas J. Downey (D-N.Y.) said of the various MX-small missile combinations being advocated these days: "They're dreaming if they think they can get the MX. We've got the votes to beat the MX."