Bob, I know the feeling of too many instruments, but sometimes there are things that you can't pass up. Just by following estatesales.net and craigslist, here's what I've picked up in the last few years (each for less than $200):
1. a 1974 Liberty Quadrille flathead five-string (pro quality);
2. a 1920s Gibson trapdoor conversion to five-string; and
3. an 1888 Gatcomb five-string.
Plectrum also has a longer neck than a tenor, right?