I'm down to my last few bits of kit as I exit the volt-nut world...
Datron 4200 AC Calibrator -- Recapped a couple of years ago. Fully working, has both voltage and current options.
I was hoping for £2000, but make me a sensible offer.
Shipping is a nightmare, I haven't been able to figure out a viable approach, a small pallet seems like the best method, but I don't have the tools or strapping needed for that to work, so my preference would be a pickup (from near Poole, Dorset), or some good other suggestions!