Info needed on Blau table radio

[miniman82]

My Nephew thought of me when a friend mentioned having this radio, but I have no info about it and know nothing about the German stuff. Therefore, I defer to the experts. He wants to know if it's a rare thing, and would like some idea of it's value. I'm thinking like $50? No idea if he's trying to sell it or just curious, but he did say that it works well. It's a Riviera, 2643 is what it says on the back. Thank you.