As far as I'm aware you do need a particular pump for the Boilermate 2000. Should be the same as original (x18). But I'd probably get the sensors checked first as they are prone to failure.
When I was an apprentice we used to use Cementone Mortar Clean for our council contracts (refurbs) to clear scale from wc pans. Worked a treat in about 1 min :shock: Goggles required :shock: :shock:
You might be able to get a few spares, not many though. Parts by Glowworm. Boilers about 28/30 years old.
Most have been disconnected by now due to the front case seal being knackered and obsolete.
If you want BG to fit the new gas valve it will have to be
1. the correct valve
2. unused.
3. in manufacturers packaging.
If none of the above, then I'm afraid you've had it :cry: