I have the following items for sale:
Adram 520 w/addon card for "Gary" and ribbon cable:
I purchased an A500 (rev 5) that had this installed. I tried to install it into a Rev 6a board, but it does not register. Put it back in the Rev 5, works perfectly (it is 1MB, so Workbench reports as 1.5MB)
I use the rev 6a computer primarily, so I have no use for the card. I do believe it can be made to work with a rev 6 and higher A500, but it is beyond my expertise to discover how

The card is in pristine condition and I just purchased a new clock battery at RS for it yesterday, so it is good to keep your time for many years to come

Make an offer!
Also have a 1.3 rom pulled from an A500. I pulled it and replaced it with a 3.1 in my machine, so if anybody has any use/needs one, make an offer as well!