Looks genuine to me.

Atari had a huge amount of components that were sold off when they closed up shop. One place in Santa Clara that bought a bunch was Anchor Electronics. I bought all their remaining NOS Atari 400/800 CPU and 16K RAM boards a few years ago. You'll find a lot of those chips still ...

If they have different tasks to perform you can divide those out and communicate between the 2 via shared RAM.

Namco did that for Galaga/Bosconian using 3 Z80 CPUs and some dedicated microcontrollers for speech / explosions. They did it with 3 6809 CPUs for all the games on the System 1 hardware ...

For some purposes, scavenging PALs and GALs might be useful. I have to say, I have difficulty throwing anything out.

If you're getting into desoldering, there are some connectors which might be worth keeping. I have a board with some SIMM sockets on which I thought might be useful one day.

GALs ...

I sent you a PM.

I do a lot of old computer and arcade game board repairs. The 6532 can be found in pinball games plus the Atari 2600 / 7800 game consoles plus in Fluke 9xxx series CPU pods so there's a demand for them.

Raymond