If you have any plate-mounted Cherry MX keyboard, you could put SMK switches into it and hand wire them. Only problem is most Alps keycaps have Alps-style rather than MX-style stabilizer insert mounts, so you might be stuck with the Chicony’s ****ty keycaps, at least for the larger keys.
It’s true though, both the case and keycaps on the KB-5181 are awful: very flimsy and cheap feeling. Pull the plate/pcb out of the case and swap the keycaps out and you instantly have something that feels dramatically better.