Just to be difficult, let me suggest a 4" S&W K-frame 38 Spl. Get a good condition used gun (or maybe even police trade-in) with adjustable sights. With no changes you can use it for plinking, IDPA/ICORE/USPSA or even CCW if you can hide it. Also, the world is still swamped K frame holsters, speed loaders, gunsmiths, etc. Unless you're planning on shooting a ton of hot or magnum loads, you'll never wear out a model 15 (or the stainless version a mod 67) or a 19 (or mod 66).
pmacb