Just an update to this in case anyone is chasing down a replacement pump, I fitted the BG pump today and got it working fine.
Straight swap on the units themselves, no issues with connectors. I had copied my coding from my previous pump before removal. When I connected to the new pump I was getting the DTC "Incorrect Control Module", so I went into the long coding section, turned off hill hold (new pump didn't have it) and cleared the code, all good.
After the coding I did all the required adaptions, and did the vagcom brake bleed. The dash lights don't go off until you drive the car, so got that done and I now have ABS again after 4 months! Just need to get through the NCT now.
Would've liked to keep Hill Hold, but was struggling to get the right pump so a working replacement unit in for 100 quid and I'm happy enough.