In case you don't know - the AP-74 .22 is in the "restricted"category. I know, ridiculous, but it is. This, of course, means it can only be used at ranges approved for "restricteds" and it cannot be used in the field.
Had one which I sold when it became restricted. An amazingly accurate rifle considering its type.
Not very many of them around and I doubt that there is much of a demand for them. If in really good condition I would think that $150 - $200 would be about right, but only if you have a range on which to shoot it.