02 Jan 2013, 15:26
The only thing that I know that looks like that is [wiki]BTC dome with slider[/wiki].
I'm recording all the cross mounts that I can measure or get measuments for, here: [wiki]Cross mount clearinghouse[/wiki]. The keyboard pictured above is not U mount (e.g. Cherry MX) — the cross arms are too long, or too thin, or both. It's also not Cherry pre-MX, as that was a non-uniform cross, a tee (one of the side arms missing from the cross), and I think fossala had a vintage cherry with bar mount (both side arms missing from the cross).