Marquette keyboard for a cardiac stress test machine. It's filthy as hell and needs a good cleaning, but has an MX lock switch, some of the most interesting plate mount Cherry stabilizers I've ever seen (and they feel quite nice too), and vintage Blacks (from what I can tell). It's almost impossible to see without a microscope or proper macro lens and good lighting, but the MX Lock does have Cherry written on the housing.
PCB porn for those of you into that:
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I'm hoping my other find proves to be as interesting and with Brown Alps...though it could be boring and disappointing.