You can try eBay. Some people buy whole games and sell the pieces off separately. That can be a good source for little bits, when you don’t want or need the whole game again.
They actually show up on eBay a lot. The key is to try different search terms. Not everyone lists them as Industrial Complexes. Sometimes you have to try Axis and Allies Factories, Industrial Factories, etc.
I posted a method of a simple calculation of the requirements for industrial chips or paper money (bucks), for each version of the Axis and Allies game. I think the results are somewhat revisionist compared to the existing sets in use. It is a good basis for everyone to configure the set that suits them, knowing the real requirements of each game. This is shown in the link below: https://www.axisandallies.org/forums/post/1635056
Its just a freaking cover name for a number of other box of plastic junk that came in boxes with rules and map, etc. It means nothing and only applies to Milton Bradley games of this type.
