You'll have a more difficult time finding an (inexpensive) small tap handle that is centered, not the taps. Even Hanson (Irwin branded) taps are fine for occasional use, barring exotic materials such as case-hardened steel. If you can find an older General tap handle, they're good quality...the new ones are iffy, sometimes concentric, sometimes not.

In the US, Triumph makes very good taps, though finding a distributor for the metric ones can be difficult. I would personally plan to have at least an M5x0.8 (which needs a small handle), M6x1.0, and an M10x1.0 (which both need a larger handle). Between those three sizes, you'll cover 90% of threading issues on a bike. Bottom bracket/pedal taps are more or less specific to the bicycle industry, due to the reverse threading on opposite sides (so, Var, Unior, Park, are pretty much the only companies selling them).

Remember to liberally oil the taps before use, or periodically during heavy use.

I can count on one hand the number of times a die has come in handy in a shop environment, as most male threaded parts are usually toasted by the time I see them. For personal use, I can see their appeal.