Sorry to pour rain on your umbrella, but... I see these now and then in charity shops and old wares markets.
Here they go for about AUD $30-$50 depending on condition. Yours looks, well, at the lower end of the list. Those few secondhand dealers who stock such old gear, usually try for more $$, but the cameras end up just sitting in the display cabinet for eons.
Sadly, they are just too much effort to restore for too little return.
Fun to play with if it still works, and it can give you some truly good images if you work at it - tho' the odd East German controls can push you off the mental cliff.