I have some Atari 2600 dupes here. Feel free to make an offer if you are interested in something.
I have 35+ positive feedback on this site.
The games are:
Blueprint
Porky's
Dragonfire
Cosmic Ark
Piece O' Cake
California Games
Encounter at L5
Sneak N Peek
Zaxxon
Winter Games
Star Wars The Empire Strikes Back
Atlantis
Demon Attack
Solar Fox
MASH
Moonsweeper
Wizard of Wor
Eggomania
Miner 2049er
Star Voyager
Towering Inferno
Planet patrol
Demon Attack
Mario Bros.