President Reagan will name White House national security consultant Thomas C. Reed and former secretary of state Alexander M. Haig Jr. to a commission to decide on a deployment system for the MX missile, administration officials said today.

The commission, whose full membership will be formally announced early next week, will be chaired by Brent Scowcroft, former national security affairs adviser to President Ford, and will include President Carter's defense secretary, Harold Brown, as a member.

White House officials disclosed today that Reagan also will name a "working group" of consultants to advise the commission, and that this group may include Henry A. Kissinger and former deputy defense secretary David Packard.

Appointing the commission, which is to recommend an MX basing plan to the president within 60 days, has proved difficult. Reagan had hoped to select the body before coming here for a holiday week, but conflict-of-interest checks have delayed the process.

Questions about Reed, a consultant to the National Security Council under White House national security adviser William P. Clark, were revived recently by a Common Cause magazine analysis of a 1981 Securities and Exchange Commission case against him.

The SEC had charged that Reed parlayed a $3,125 investment on stock options in Amax Corp. into $427,000 in profits after talking to his father, a member of the Amax board, who knew that Standard Oil of California would make an offer to buy Amax that dramatically increased its stock value. Reed, a former secretary of the Air Force, agreed to repay the $427,000 without admitting or denying the charge.

When asked whether Reed's selection for the MX basing commission would be controversial, White House officials said Reed was cleared for his present job by both the FBI and the White House counsel's office after the SEC case was settled a year ago.

"The checks by [White House counsel] Fred Fielding's office determined that there was no malfeasance on Reed's part," a senior official said.

An appointment of Haig may help smooth ruffled feelings since he resigned as secretary of state last summer and was replaced with George P. Shultz. Haig's name, like Scowcroft's, was suggested by Clark, who once served as Haig's deputy at the State Department.

Though there is still no love lost between the White House staff and Haig, his appointment to a commission vital to Reagan's defense policy was a signal that the administration needs his cooperation. Some administration officials have said they believe Haig is a prospective candidate for the Republican presidential nomination in 1984.

White House officials emphasized that the administration is not wedded to Reagan's most recent proposal for closely spaced "Dense Pack" basing of 100 MX missiles near Warren Air Force Base in Wyoming, which essentially has been rejected by Congress.

Skepticism also has been expressed by congressional critics or Pentagon officials about many of the other potential basing plans likely to be considered by the commission, ranging from putting MX missiles into hardened silos now occupied by Minuteman missiles, which MX is to replace as an intercontinental nuclear weapon, to deploying them on ships, submarines or even specially designed planes.