[codefox1]

Agree, these sets are not too critical about specs; anything with at least 400 VCT winding at 50 or more ma rating should be fine. It's always OK to use a replacement with a higher current rating, if it physically fits on the chassis. If you are going to use a 5Y3, your replacement transformer must have a 5 volt 2 amp winding. You could also use a pair of 10 cent diodes instead of rectifier tube.

Assume you are going to or already have replaced the electrolytics and paper capacitors. Add a fuse (1 amp should work,) on the AC line for safety. Yeah, check the wiring and field winding too.