Support ISA cards?

I was wondering if anyone knows of a large computer vendor who still offers towers/mid-towers with ISA slots? I just received some ancient computers that I’m going to have to support, and each computer has 3 ISA boards that are used to run test equipment. I’ve browsed the Gateway, Compaq, Dell, and HP websites and I’m having trouble finding any ISA expansion slots. As a last resort I can buy components (board, cpu, ram, drives) and build a system, but I’d rather have a decent support servicebecause I won’t have much time to troubleshoot these machines when we have trouble with them. Anyone know of a large (or even medium) sized computer source that still offers ISA expansion slots?

Thanks
Charles