Cuba today approved the dispatch of a flotilla by Miami's Cuban exiles to pick up some of the thousands of would-be emigres who took refuge in the Peruvian Embassy.

The exile have already chartered more than 100 boats and the government announced that two vessels had already arrived at the port of Mariel just west of Havana.

[News services quoted U.S. Coast Guard spokesmen in Miami that two small boats had already returned to Key West, Fla., from Mariel today with 40 refugees.]

A flotilla landing here would be a repeat performance of the massive exodus of 1966, when a stream of vessels of all types came from Miami and hauled away thousands of refugees from the port of Camarioca.

Often overloading their craft, boat owners then made fortunes by charging exorbitant fees and Cuba was able to reduce internal pressures on its young socialist government.

Although Cuban officials already had said privately that the Miami vessels would be permitted to land, a muted invitation came today, buried casually deep down in an editorial of the Communist Party newspaper Granma.

Referring to vessels "coming from Florida to pick up antisocial elements," Granma said that "of course we are not going to receive them with cannon fire since they come on a peaceful mission and we have no objection to having them take them [the regugees] away," Cuban officials said this was tantamount to an invitation.

Granma did not make clear whether it only endorsed the departure of the 10,500 refugees who stormed the Peruvian Embassy two weeks ago. No mention was made of others who may aspire to leave Cuba.

Only 1,500 of the 10,500 have refused to leave the embassy and accept the safe-conduct passes the Cuban government has given to 8,400 would-be emigres. The people now refusing to leave the embassy, Western diplomats believe, may have criminal or other charges pending against them, or they simply do not trust President Fidel Castro's word that they may leave the country from their homes.

The newest Cuban announcement is causing waves among diplomats here who had expected a massive airlift to Costa Rica, where refugees would be cleared before traveling to other countreis for permanent asylum.

Castro, who is known for his unorthodox and unpredictable approach to problem-solving, on Friday suddenly decided to cut off the Costa Rican air corridor and its attendant humiliating publicity. By then, only about 800 people had reached San Jose, the Costa Rican capital.

The Associated Press quoted a Costan Rican Foreign Ministry official as saying that Cuba told San Jose it would respond Wednesday to Costa Rice's request on Sunday that the evacuation flights be resumed.

[In making the request, Costa Rica had offered to accept all would-be exiles instead of the 300 it had agreed to take earlier. When he suspended the flights, Castro said the refugees would be allowed out only if they flew directly to the countries that agreed to take them.]

A flotilla picking up refugees in the port of Mariel conjures up for U.S. officials a chaotic scene of Cubans boarding Miami-bound craft without being screened and documented by the U.S. Interests Section here.

"It will be up to the Coast Guard and Immigration at the other end; they're being put on the spot," one American source said. "I just don't know what their attitude will be."

The government-controlled Cuban press has focused its attention on the arrival of impoverished Haitians in Miami who are threatened with deportation, allegedly because they are "economic" and not political refugees.

The Haitians "are the true measure of Carter's human rights policy. They live under a repressive feudal regime . . . but they are not admitted as political refugees while the United States stimulates the emigration of delinquents from Cuba," Granma wrote today.