Virginia Republican gubernatorial nominee J. Marshall Coleman, still seeking to unify conservatives troubled by the GOP ticket, will visit the White House Friday morning to receive a political blessing from the nation's top conservative -- President Reagan.

While no announcement has been made, knowledgeable Republicans here and in the White House confirmed today that Coleman and the rest of the ticket, lieutenant governor nominee Nathan H. Miller and attorney general candidate Wyatt B. Durrette, will meet for 30 minutes with the president.

The meeting will be preceded by a strategy session with White House political director Lyn Nofziger and state Republican political operatives.

The session will give Coleman and his running mates their first direct opportunity to capitalize on what many believe is the Virginia GOP's ultimate weapon in this year's close race -- Reagan's popularity with state voters.

The photos and video tape to be shot Friday will be appearing in brochures and television ads for the rest of the campaign, as will the often-repeated Coleman theme that the contest between him and Democratic Lt. Gov. Charles S. Robb is, in effect, a referendum on the first year of the Reagan administraion.

Coming just two weeks after a wild and divisive state party convention battle over the ticket's second spot, the meeting is also designed to help heal the wounds of the GOP's conservative wing. Many in that faction have lingering doubts about Coleman's conservative credentials and were angered when their favored lieutenant governor's candidate, state Sen. Herbert Bateman, was buried under an anti-establishment avalanche at the convention.

Robb spokesman George Stoddart, noting that the Reagan administration already has dispatched Vice President Bush, Budget Director David Stockman and Treasury Secretary Donald Reagan to Coleman fund-raisers, called the White House meeting "just the latest attempt to take the focus of the Virginia campaign off Virginia . . . They're hurriedly running around to try to get help with conservatives who have good reason to be concerned about them."

Robb, who calls himself a fiscal conservative, campaigned for Jimmy Carter here last year, albeit with little enthusiasm, and has since said he has little or no quarrel with Reagan's aggressive program of federal cutbacks. h

Stoddart cited a 1977 newspaper article that quoted Coleman denouncing as an "intrusion" a similar Reagan endorsement of Durrette, who was then Coleman's opponent for the attorney general's nomination. (Coleman later won the position.) Coleman was quoted as adding, "I hope [Reagan's] endorsement does as much for Durrette as his endorsement did for Sen. Richard Schweiker [Reagan's losing vice presidential choice in 1976.]"

A Reagan letter endorsing Coleman was prominently displayed at the state convention, at which Coleman staff members had hoped for a surprise visit from the president. That visit did not occur, one White House aide said, because Reagan's schedule was overloaded. Virginia Republicans still hope for a presidential visit sometime in the fall.