It might be as old as I am (probably not, I'll bet my dad bought it at a yard sale), but it still works fine, the trick is finding belts for it.
The belts are 2.5 by 16. Amazingly enough Ace hardware had a replacement belt for it, but neither Home Depot nor Lowes carried that size. Ace sells two of their "Ace brand" belts for $5.50 (40 grit - extra coarse).
Given that this is a belt sander, I am using it for bulk material removal (like stripping paint), not fine finish sanding. I have a random orbital sander for finish sanding. So, I see a need primarily for coarse aggressive and durable belts. I can find them on Amazon.com (be sure and search both for 2.5 by 16 and for 2 1/2 by 16).
A recommendation that looks good, and I want to try is:
They typically charge about $1.00 per belt (or less).Tom's home page / tom@mmto.org