Here is a larger drawing, note that this is just a small building block and idea of how the 2 FV-1 chips could be used, there will still be a lot of stuff to add to make a complete effect.

1st FV-1- left output will carry 800ms delay to output mixing

1st FV-1- Right output will pass 800ms delay to the 2nd FV-1

2nd FV- 1 left output will carry 1.6 second delay to output mixing

2nd FV-1 Right output not used (possibly use to add feedback)

The Eeproms you linked to are the correct ones.

I hope this gets you started with your plan. I suppose there are many other ways to build what you are looking for and this is just one option.