As these seem to be standard laptop hard drives with some bits screwed on, I was going to try and snap up the next drive I see cheap on eBay and screw the ultrabay fittings on, but it occured to me that the slot at the back might vary. A few drives on eBay list 'pata' in the description and I'm guessing by age that that's what I'd need? Also that the top right hand side may need to be of the 'sawn off' type to fit, or not. I got a CDrw and a DVD-rom drive with my recent second hand T22 but the CDrw drive seems quieter but works badly more often, whereas the DVD drive works fine but could be quieter.

If anyone here can confirm my assumptions, thanks.

Find all the differences here: http://www.thinkwiki.org/wiki/Ultrabay