Have you looked on the CM site to see what accys are available? Generally if the end supports are not in the case to begin with, then there aren't any but you never know. And places like
http://www.CyberGuys.com may have those fingers (called Cardkeeper) that are designed to hold cards in the slots during shipping, etc. Could give some support, but not at the end of the card. I've not seen generic card end supports as they need to be mounted and no way to tell what any given case has in the way of surfaces for mounting. Otherise, you'll just have to rig something maybe you could rig one of those cardkeepers to work at the far end.
.bh.