I would say your coin falls into the Scarce category. https://coinparade.co.uk/sheldon-rarity-scale-ways-define-rarity-coins/
Amazing grade and because there were only 500 minted. Where did you get this coin ? In proof 65 it is worth $1,500. Not sure how much your coin in proof 68 is ? Guessing $2,000-3,000+ wait for more opinions...