just picked up three new superior electric Powerstat vairable transformers, type 12C. These are rated 240V .70 amp, and can be wired to have a 10% voltage increase at the output if you like. Of course you can use them on
110, it's the current that matters. These particular units seem to list for $108.14 new (see
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) so I think a fair price is $30 each - let me know if you would like one - or more.