I remember going through the same process. I did find a couple of othe manufacturers that made PCI Expansion Chassis but I don't remember theyr names or websites.
Someone on this site gave me great advice. If you are patient they show up on Ebay at a fraction of the cost. I got my perfectly functioning 7 space chassis for $400
Failing that do a google search under PCI Expansion Chassis or derivatives of the term. Good Luck
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