Holton tubas have often been great. There's someone on Tubenet who's refurbished one of the old large ones (maybe a monster?), I think added a valve to it, and uses it as an orchestral instrument. A 4-valve Eb like that could be a really sweet horn in a community band if you can put it in good shape. Learn the Eb fingerings. Although I'm playing bass trombone full time now, I used my Wesses Eb in community band for about 5 years -- really love the Eb horns. The 4th valve should let you play anything you come across, and the false tones on the Ebs are usually excellent as well.
Gary Merrill
Wessex EEb Bass tuba (DW 3XL or 2XL)
Mack Brass Compensating Euph (DE N106, Euph J, J9 euph)
Amati Oval Euph (DE 104, Euph J, J6 euph)
1924 Buescher 3-valve Eb tuba (with std US receiver), Kelly 25
Schiller American Heritage 7B clone bass trombone (DE LB K/K10/112/14 Lexan, Brass Ark MV50R)
1947 Olds "Standard" trombone (Olds #3)