Get something WIDE and sticky. depending on your power output you're going to be losing traction with the sickness now. minimum 285\35\19 in the rear.
they're 44 offsetIMO even a 285 is pushing it on a 9-1/2" wide wheel; I would stick with 275.
But even with appropriate tires sizes for the wheel widths, I would have to know the wheel offsets to know for sure what will fit.
Go with a 275 then. As for actual brand, I'm running Bridgestone Potenza RE-70's and I like 'em.they're 44 offset