Replacement lights for Dynaco QSA-300. Good amp?

I just picked up a Dynaco QSA-300 for 80.00 on the local craigslist and one side of the display is burned out. I'm trying to find some information about replacement bulbs and where to find them and I can't seem to find anything. I'm really excited about this amp. I know very little about it but it seems pretty damn serious! There's a low hum coming from the amp and I've yet to hook it up to speakers. We'll see! Thanks for any help!