Yes unfortunately Lomo zooms do command a high price, if it seems too good to be true it probably is. This forum is a good place to buy for the most part. Tito is a good guy he's been doing business on here for a while.
I would say anything this old and Russian would need to be serviced to get the best out of it anyway. If your budget won't stretch, go with a Sankor or a Kowa, you wont go too far wrong.