A good source for an inexpensive Isolated Variable AC Power Supply

[vortalexfan]

Hello everyone, I've been trying to look up an inexpensive (under $50) Isolated Variable AC Power Supply (like the one that Shango066 uses in his Videos or like the Heathkit one that Radiotvphononut uses in his videos) and I've not found anything so far, and what ones I have found they wanted over $300 or more for them and some ridiculuous amount for shipping costs that brings the cost to almost $800.

The reason why I ask is that I have a 1947 vintage Westinghouse AM/FM Bakelite Tabletop radio thats an AA6 set that is receiving absolutely no signal whatsoever on either AM or FM and I want to try and hook my signal generator up to it to check the front end out on the radio but since I don't have an isolated power supply to hook the radio up to, I dare not try and work on that radio right now otherwise I might fry my test gear and I don't want to fry my signal generator.

Anyone on here have any suggestions for a good isolated variable AC power supply that I could use to plug my series string radios into for troubleshooting purposes?

Thanks for your help.