There are lots of good sources for small tools besides the Lee Oskar kit. Micro Mark is a great one for small screwdrivers, nut drivers, wrenches, files, pin vices and the like. I don't know exactly what kind of work you want to do, but a lot of stuff can be had even from places like Harbor Freight. I don't suggest using a steel tool (like a paper clip) for adjusting gaps, because the hard metal can scratch reeds. That said, I sometimes use the backside of a curved dental pick for that job. Instead of the rather pricey sanding wands and replacement belts, I like to use 400 grit emory paper cut into 3/8" strips, wrapped around a piece of pencil eraser. Cheap, fast, and effective. Brass pick tools can be hard to find, but I've recently started making my own from 1/8" brass rod from Small Parts, and a little time at the disk/belt sander and anvil. Many thanks to G in New Zealand for both the sample, and the advice on how to make them.
-tim