I missed this thread, though it looks like you've got the answers you're looking for... even though you may not like them.
Just a thought; lets say you're getting a really great deal on the mystery amp.
Check the price of having its transformer swapped with one of the correct voltage.
Or, still assuming it's such a great deal, sell it to someone that has the proper 240v outlet.
Otherwise take a pass on this one and let your girlfriend hold onto the credit card for a while.

I understand, sometimes the deals are irresistible.