Good Sounding Speaker that Won't Attract Thieves?

Moving my painting & drawing studio (formerly our living room + den while the wife was at work) to a 14' x 24' metal barn and am basically looking for a pair of speakers with a sonic personality generally similar to a JBL Century 100 that I can pick up cheap at a rummage sale and run with a plain Jane 2 channel receiver. Preferably something that's a sleeper, soundwise, but which which, cosmetically, practically screams to a crack addict, "You probably couldn't even trade me for a six pack of beer." Any suggestions?