Re: do they make a bushing for the upper gimble ring to housing?
From your question it looks like you have vertical play on the lower swivel pin. If you look at where the lower swivel pin goes through the bottom of the gimbal ring, you will see a washer on top of the ring. There should be between .002" and .010" clearance between the washer and the gimbal housing mount. This clearance is adjusted by loosening the clamping nut on the steering arm shaft and tightening the upper shaft nut, which raises the ring. Service manual #6 section 4B, major transom work describes the procedures involved. You might be able to do it from inside the boat with the engine out, otherwise you have to drill holes. If you have side to side play, try retorquing the gimbal clamping bolts (the two bolts upper part of ring) to 55 ft lb (should be done every year). If you have no side to side play, your gimbal ring and transom plate are probably OK. Mine had similar play this spring, tightening the upper swivel pin bolt brought it into spec. Good luck