Vintage Sylvania tube clock radio help please!?

I was recently given an old Sylvania clock radio and I am wondering if anyone knows were i can find out more about it? I fixed the power plug-in and got it to light up, but i need to fix the radio knobs and maybe a couple things interal, I have tried lookin up the model number but it has 2 numbers 1 over the other, i cant find either online, 1 faded stamped number is 643B, the other is a sticker like one with CW-229174 on it, can anyone help me find places to research this neat clock, or fill me in on the era and stuff it was in?