I bought a '59 tweed Deluxe for $5 at a garage sale in 1995 and ended up replacing the OT. I don't have it anymore; I sold it for $1K a month later. My friend picked up a '66 VibroChamp for $20 in a junk shop in 1990. I replaced some caps and the bias resistor to get it going. He still has that one.
There is no substitute for Sound Pressure Level