Thanks for the offer. I no longer have any Masters though, only two Model Bs (Issue 4 and Issue 7) and one spare Type 1 keyboard. The latter machine is tidied away, kept as a spare for when the Issue 4 machine finally dies. It has "Issue 4 Disease" where it keeps freezing, and the mean time between freezes decreases with use (until it crashes during POST) and increases with inactivity. No-one else ever recognises this symptom, but it's my third Issue 4 machine with it, and the behaviour pattern points to a bad capacitor somewhere.
I thought I'd mentioned the nasty Master keyswitches, maybe that was in the e-mail to 8bs. Masters have a very similar switch to the B, except they all wore out. I gave a friend's brother my only Master with a fully working keyboard along with the 20 MB HDD, mouse and Quest Paint, and I don't expect to ever see it again.