Through a lengthy turn of events, I acquired this beautiful B15N recently. From what I understand, the serial number puts it at 1966. From my tech's insight, he said the only things that aren't original are a couple tubes, and the Fliptops Power Transformer, which he just installed. The slip cover is even supposed to be original! I got it home last night, and before I fall in love and get attached, I would love some insight into what an accurate appraisal would look like for this. When I received it, it also came with 2 other Output Transformers - which are untested. I'm not sure if that matters for the appraisal, I might sell those separately in an 'as is' auction. I also still have the original shot Power Transformer. You can take a look at a few photos below, or skim through all 60some here: Ampeg B15N pictures by gearforsale - Photobucket Any input is very much appreciated!