Now on eBay
I don’t know the seller or endorse the product, but here is a cool late 60′s bass amp built by Valco for Gretsch. Solid-state rectifier, 12AX7 preamp tubes (I believe?), 6L6 output tubes and a Jensen 15-inch speaker. I have not heard these amps myself, but the seller claims they are similar to the Supro Thunderbolt, which was used by Jimmy Page and Brian Setzer.
UPDATE: This amp sold for $400.