Wow, I completely forgot about this post! Were you able to locate a cabinet to get the dimensions?Great to hear the amp works well and sounds good. Old tube amps seem to be in demand these days. The new boutique stuff is pretty expensive, although the new technology is truly awesome, with a lot of flexibilty in tonal settings and modeling effects.
I recently restored a CMI Electronics SG-410 (c.a. 1973) that I bought new in 1976. The power tubes were a bit hard to find (two RCA 8417s) but I won an eBay auction for a decent price. Then I located a really good tube amp tech locally who went through the whole thing for almost nothing.
I play a Stat Plus Deluxe and a Les Paul Classic (I prefer the Strat, if you can believe that!) and I'm really enjoying the warm sound of the tube amp. I've been using a solid state Fender Stage 100 as a replacement (into two DT-412 cabs). It has tons of power, and Fender did a decent job of making it sound almost like a tube amp. But for home use why do I need to get knocked across the studio?
About the same era as the Silvertone, Wards (Airline) made some big cool-looking tube amps. I had the head from a GVC-9052 at the same time I had the 1484. I've been able to find pictures of both on the 'net (just for the sake of nostalgia).