I recently bought the AEB-1 with the Bad Ass Bridge and p-bass pups on eBay for $1925.
I have discussed this bass with Bruce Johnson and it turns out to be a prototype built in June 1966. He places it's serial number in the 030's. Since the tailpiece was removed during the mod, we will never know the actual number.
Bruce puts the value at $3,000 with the mods. It is in very good shape. It doesn't suffer from the paint deterioration of the production Ampegs.
It plays well with decent action. The intonation is dead on. The only problem is a buzz at the 12th fret of the A string.
I am not comfortable touching the truss rod. I could just adjust the saddle on the A string but I want Bruce to look at it. So, I will probably ship it to Bruce for a good set-up. I will probably also replace the p-bass pups with a better set.
I had been looking since 1970. I have bid on many that have come up on eBay but have always dropped out when they hit $2,000.
This time it went my way. I couldn't be happier.
Good luck on your search.