Reply from SEAS:
Can’t say that we recognize these, however it might be a small production specified for a customer at some point. It certainly looks like SEAS, but we cannot say for sure.
Med vennlig hilsen / Kind regards
So a well done DIY...
It's an auction website. Roller Auctions in Denver. Here is another picture. 2 versions along with a single Onkyo 910 and a Single Bose 601, Series 1. Like I said: just can't find it in the memory. Probably a DIY project and my old memory playing tricks