I've got a very small set sold by Lyman. It's called their Compact Driver Kit, and it comes with a short standard driver and a very handy reversible ratchet ball driver- just the ticket for rifle stock butt-spacer screws with 3" of thread. Both drivers take interchangeable magnetic tips. It was not expensive, and is worth more than I paid.
http://www.lymanproducts.com/lymanproducts/tools.htm
'coach