[Jeffhs]

That Sylvania TV has a very nice cabinet. I have two end tables and a coffee table in my apartment with the same type of legs as your TV has. That design must have been popular in the '60s-'70s, and made a comeback in the late 1990s when I bought my furniture (I was moving to an apartment, the one I live in today, at the time, and wanted to make a fresh start).

That your TV's cabinet has absolutely no scratches whatsoever on top is wonderful. Your set's former owner(s) must have taken extremely good care of it, which is good. I've seen console TVs with all manner of dust, dirt, scratches, etc. on them (I've owned a few, mostly trash finds; they stayed in the basement of my former home, of course), and again, your Sylvania console, as scratch-free as it is, is a sight for sore eyes.

Back on topic: I'm not sure what tube substitutes for a 3A3, as it has been years since I worked on TVs of any kind (my apartment is very small, so I limit the little restoration work I do to small radios). However, the list of subs for the 3A3 I saw in another post seems quite comprehensive, so one of them should work.

I'd be extremely careful with a tube such as a 3A3, as the filament of this tube carries extremely high voltage (especially in color TVs), on the order of kilovolts, not just three volts as the type designation would have one believe. These tubes get their filament voltage from a single turn of exceedingly well insulated wire wrapped around the laminations at the base of the flyback transformer.