I posted a picture of the keyboard on this thing (along with a request for recommendations) a while back, and figured a few of you might be interested in the followup.

They unit is working really well now, and the keys feel substantially better. I still think they're a little stubborn - they're a lot of resistant right at the top of the stroke, particularly if you're not quite pushing straight down on the keycap. Ideally I'd remove the switches to lubricate them individually, but I'm hesitant to actually pull them out since they're fitted using 40+ year old plastics that may have become very brittle in the meantime.

Anyway, thanks /u/jk_pens for their advice! It worked out great.