I had a similar problem for my Olivetti M20 ( Z8000
based ).
I think it was Tony that pointed out that the TRS80 5Meg hard
disk drive contained an almost identical controller to the SA1000.
For the interface card=2C I wired up my own on a wire wrap board.
Err, aren't you confusing the WD1000 series controllers (which were used
in the TRS-80 drive boxes) with the SA1000 8" winchester drive, which has
a 'raw' interface, IIRC on a single 50 pin connector?
-tony