This is where it all started...

I found this box of tiny solenoids in our makerspace.  No datasheet, but by experimentation 1.5V to 2V seems to work on them.  Alas they're the pull type, so I had to rely on the included spring to hit the glockenspiel bar.

Designed to be printed without supports!

I screwed up the transistor footprint so I had to bend the leads and solder them upside down!