Electric baseboard thermostat

Not sure if I'm in the right place for this question or not.

My house is mostly steam heat, but prior owners put on a small addition And turned an upstairs closet into a bathroom. These new rooms have electric baseboard heat.

Heaters work fine, but thermostats are crummy. Especially in the bathroom. It only functions as an on off switch at the moment so I want to replace that one.

I'm handy enough not to kill myself swapping it out, but not well enough informed to pick out a replacement.

Any thoughts?
Attached are pictures of the the spec label on the heater (the bathroom only has one of the smaller baseboard units) and the existing thermostat.