Once upon a time, I got an 18 GB 1/3 height (i.e. about 50% again thicker than your standard 3.5" hard drive; the same height as a standard desktop CD-ROM drdive,) 10,000 RPM SCA (80-pin,) hard drive dirt cheap. (It was still a 'current' drive at the time, and I got it for about 25% retail value because the guy hadn't a clue what he had bought it for, not even having a SCSI card, and just wanted to be rid of it.)

I found a rather low-end generic SCA->68/50 pin adapter, and slapped it in my workstation. Worked great. Noisy beast, generated more heat than my main CPU, but it worked great.

After that workstation got retired, I even put it in my SE/30 for a while. Worked fine. (Didn't run it for long periods of time for fear of burning out the little SE/30's power supply. Ended up powering it externally, and adding another fan to the SE/30 to run it.