Styrofoam "saws" well, use a coarse hack saw blade. It also cuts with a very sharp, thin blade knife; but it makes a big mess and will keep on making a mess, I would not use it.
Look into ready made "equipment" cases for photographic equipment. It usually comes full of closed cell soft, but firm foam that is easy to cut.
Ebay has lots of them. Try a search for "aluminum hard case"; like this one:
https://www.ebay.com/itm/C402-Alumin...oAAOSwg0BZzso2
You can always line the hardwood cut outs with felt strips.