The San Francisco Chronicle JUNE 7, 1991, FRIDAY, FINAL EDITION PERSONALS Leah Garchik M.C. HAMMER PAYS FOR SINEAD'S ONE-WAY TICKET Rapper M. C. Hammer was so outraged by Sinead O'Connor 's repudiation of ''The Star-Spangled Banner'' -- perhaps he was bothered, too, by her telling Rolling Stone that she didn't think his music was worth much -- that in a recent interview on ''Entertainment Tonight,'' he said he thought she ought to move back to Ireland. He'd even pay for her ticket, he said. O'Connor took him up on the offer, reported the newsletter TV etc. When she flew to London in early May, she sent Hammer the bill. The rap master put his money where his mouth was, promptly reimbursing the Irish pop star $ 2,624. No note was enclosed, but the check was marked ''one-way ticket home per Hammer.'' Hammer's publicist, Maureen O'Connor , confirmed yesterday that this is true, but added that that the two stars don't disagree on everything. They both participated in a recent British-based fund-raising concert for Kurdish refugees, she said.