Not infrequently Hickok tube testers appear for sale for reasonable prices at forums and sites which serve the antique radio collecting community. For example, this listing offering a model 534 for $325 appeared just three days ago, although as you can see in the subject line the unit has already been sold.
Periodically Googling "antique radios" + "Hickok" + "tube tester" could very well pay off, eventually if not sooner!
Best regards,
-- Al
Periodically Googling "antique radios" + "Hickok" + "tube tester" could very well pay off, eventually if not sooner!
Best regards,
-- Al