how deep? they make rackmount shipping containers, this one is 20" deep, though i've seen more. we used to have on that was 8ish units and deep enough for full servers, but I can't find it right now.
https://smile.amazon.com/Tripp-Lite-Equipment-Transportation-SRCASE10U/dp/B07GX5H77V
My recommendation is the Tripp Lite case that was posted earlier. I believe the CHENBRO RM42300-F will fit in it. Verify all specs though obviously.