Wow, I guess I have something unusual here since nobody responded lol. I did see a similar amp to this on the bay the seller said was from the 70's. It was a combo, the same color but with a 10'. The seller added a new speaker and back to the amp as well as some other things and was asking $150.00
Vintage Harmony H1618 Amp | eBay
I played through it last night with the LP and some effects and it sounded good to me. I used a crybaby and a Boss SD-1. I guess it's a keeper.