John,
I had a similar requirement for a small mag drill, drilling some inaccessible areas on my engine. My old mag base drill was too large and unwieldy to get to the areas I needed to drill.
I ended up buying the evolution mag drill from Machine Mart, I assumed it would be Chinese crap but would get the job done, and I could hide it in the cupboard. It turned out to be pretty good and a lot more useful than my back breaking "proper" mag base drill. We have used it loads since...
https://www.machinemart.co.uk/p/bora...SABEgIt2vD_BwE
Cheap and cheerful, and has proved reliable.
Dave