Going by Racketboy for PAL NES games;

Mr. Gimmick: $600 – $750
Vindicators (Australian HES version) : $600 – $710
The Flintstones: Surprise At Dinosaur Peak: $600 – $750
Jetsons: Cogwell’s Caper: $ $300 – $400
Parasol Stars: $50 – $80
Banana Prince: $45 – $75
Noah’s Ark: $35 – $60