Small repairs like the above can easily be done hand held. It's when working of deep dings or large areas (bracelet clasp are surprisingly time consuming) that a motor or a bracket really becomes really a saver. Don't forget to wear cotton gloves and work inside a cardboard box because is a bit of messy work.
I do actually have a Dremel. It’s a rechargeable one.
I guess I need a bracket to mount it to a desk and something to hold the hard felt wheel.
Hopefully Dremel make both of these attachments.
https://mb.nawcc.org/threads/rack-strike-elements.84179/ There is also a thorough description an two train and three train clocks to be had at the above link On a two train that strikes The hour and Half hour the cam on the canter wheel behind the snail cam has two extensions the three train has four as it strikes the quarters and the hour.
That is a motor as I have, beside that you can get it for much less on AliX, rotary tool means something hand held like a Dremel, Proxxon to mention brand names, but even a Chinese no name is OK, or a drill on an improvised support. Results mostly depend by case in question and technique, if you only have to restore you few pieces it's pointless to spend much. Get also smaller wheels as it's easier to do precise work and avoid edges.