Jim Plunkett has offers from six NFL clubs, his attorney says. The vet quarterback, let go by the 49ers, hopes to sign with one by Tuesday . . . Bobby (Vaga) Bonds is all but sealed for delivery to the Indians after the season, they're saying in Cleveland. The recent shipment of outfielder Johnny Grubb supposedly is installment one from Cleveland GM Gabe Paul toward acquisition of the player he obtained for the Yankees in 1974 (trading Bobby Murcer), then dealt away in '75 (for Mickey Rivers and Ed Figueroa) . . . Freddie Patek, Kansas City's 5-4 shortstop, is in the doghouse with his teammates. Royal players whisper, "We feel like he's let us down" - dogging it, they say, by staying home from road trips to nurse a virus while they play hurt in the pennant chase.Lack of pluck doesn't sound like Patek . . . Just as Jerry Reuss and Bruce Kison have begun contributing to the Pittsburgh pennant push after all but lost seasons, John Candelaria - the pirate's 20-5 left-hander of 1977, 10-11 this year - says his arm is so sore he may not be able to pitch any more this year. Skipper Chuck, Tanner nevertheless has him down to start against the Phillies Tuesday . . .