[codefox1]

So far as I know finned selenium rectifiers are no longer manufactured except maybe for code compliance for ancient elevator repairs and the like in certain cities, and of course by our dear old government.

Meanwhile elsewhere on Earth, generic 1N4007 should be fine, and costs less than a dime. Of course the silicon replacement will result in a higher B+ voltage which must be ultimately tamed with a resistor, preferable chassis mounted heat dissipated Dale type. Many of us will start out with 100-150 Ohms and measure carefully whilst bringing the recapped and recarbed set to life. Add a fuse.