[PC] Steam - Atari Vault 50 Game Add-on Pack - $3.75 - Fanatical

This gives you another 50 Atari games. As it is essentially a DLC you need Atari Vault already to make use of it.

From the website:

Get 50 additional classic Atari releases never before available on PC!

These rarities include 14 vintage Atari arcade games from the 70s, 16 Atari 5200 titles, 12 Atari 2600 games from M Network, and 8 prototype and limited-edition homebrew games for the Atari 2600. As with the original 100 games in Atari Vault, enjoy a richly configurable experience, online multiplayer, and scans of original manuals and boxes.

Games in this add-on collection:

14 Arcade games: Avalanche, Atari Baseball, Atari Basketball, Canyon Bomber, Destroyer, Dominos, Fire Truck, Atari Football, Maze Invaders, Monte Carlo, Pool Shark, Sky Diver, Atari Soccer, Super Bug

16 Atari 5200 games: Asteroids, Centipede, Countermeasure, Final Legacy, Micro-Gammon, Millipede, Miniature Golf, Missile Command, Realsports Baseball, Realsports Basketball, Realsports Football, Realsports Soccer, Realsports Tennis, Star Raiders, Super Breakout, Xari Arena

12 M Network games for the Atari 2600: Air Raiders, Armor Ambush, Astroblast, Dark Cavern, Frogs and Flies, International Soccer, Sea Battle, Space Attack, Star Strike, Super Challenge Baseball, Super Challenge Football, Swordfight

8 prototype and limited-edition homebrew games for the Atari 2600: Adventure II, Aquaventure, Frog Pond, Holey Moley, Motorodeo, Saboteur, Wizard, Yars' Return

Enjoy!