I've not found anywhere else yet and to be honest it depends on what you want to fit inside it. I see from your signature that you have a m10000 but that case takes a Celeron based MB which has a different layout of connectors on the back.
Other thing is that I believe the TRC case is smaller than 1din aperture height and width. The casetronic C134 at www.cartft.com might be a better solution as they reside in Germany.
The only other suggestion I can make is that I know this MIS Mini PC is due to be sold in the UK as it appeared in a CarHifi mag a few months back. They are not cheap though as suggested pricing for complete system inc VGA screen & SW was £1600
I bought a GPS reciever from this guy with out a problem, and he is also selling these for about $530.00 complete. http://home.wi.rr.com/gpsthings/ The case is made by casetronic. The model is 134 or 136. They can be found on ebay every once in a while also. Try the xenarc website as well.