Second-hand Keystep v1? Now that they've released the 37 with new features, people might offload the old one like I did. They did black ones of the v1 Keystep, but they might be hard to find. The Microlab looks to have the same keys but rather garish colourways.
I didn't hate the Korg Microkey I used to have, but it's not got the DIN or CV outs, which I later found I wanted.