The largest 50-pin SCSI drive I have ever seen is a 18GB Seagate (Full Height), and I have it installed in my A3000T !
I have a 36GB half-height 50-pin SCSI-2 Fast (Seagate Barracuda) I bought new about two years ago in my SGI Indigo 2. :-)
Seagate was still making the Barracuda line with this interface up until fairly recently.
I imagine you could use one of the newer Barracuda drives with the 68-pin interface and one of
these adaptors.
