BBC masters (some) have + mounts that with some dremelling fit cherry stems. Done it myself mate
Awesome, I knew I wasn't the only one to try and 'cherrify' those old keys that use something resembling cherry's + with just a bigger cilinder surrounding it!
And since Rip mentioned the Selectric, I'll take this chance to mention both my fleamarket (mis-)buys:
*an Acorn Electron (BBC master's little elcheapo brother), cut the round part off of the stems on the front and back; now fit cherry, but damn are those high (and slightly wobbly on the 1.5u keys)! But quite awesome keys for sure.
Will probably use the casing as well at some point (well, the top half of it probably, seeing how it'd be too high for comfort otherwise)
*an IBM Selectric II, and being as unexperienced as I am, I figured the keycaps would require just some slight modding to fit cherry's.. also not aware that it was an *electric* typewriter I'd figure I'd never use that tank, hence just brought the keys along. As soft as the Electron's keys are, so hard are these sobs; tough as nails I tell ya. Haven't managed to make them fit nice and easily so far. Some day, maybe.
End of story, Electron switches are shite (perhaps Alps shite, saw some pics by someone lately that resembled those pretty closely), but the caps are bloody awesome. Pretty loud though, still prefer the sound of the thin pbt on the mx11800 here.