@autospec Hey Will, did you check with ADM Metal fab in NJ, they do audio enclosures, stainless, drill holes, punching. Best of Luck.
http://www.admmetal.com/metal-fabrication-cold-rolled-steel-audiophile-chassis.html
STAIN-LESS STEEL.......DYNACO CHASSIS'S......ST-70 and MK III
I need some help getting some custom made stain-less steel chassis made........Of course none of the people selling them retail will tell me anything, and I can't pay list price for them , but I will buy larger amounts of them.....They would be the basic Dynaco style but with different holes......THANKS