I would recommend the Forster Benchrest die set for the 6.5 CM.
If you are loading for only one rifle, send the sizing die to them along with a few fired cases and they will hone it out so it matches the fired brass and doesn't overwork the brass for a nominal fee.
The Forster seater dies are my favorite. The benchrest version is the same as the ultra, just cheaper without the micrometer markings on the top. I find I don't use the markings, so save a decent amount of $$ by going with the benchrest version.