7mm-08 will work for the 7-30 with a little modification, 6.5x55 should work for the 6.5JDJ by shortening the tip of the pilot. A washered 375 Win should work for the 375JDJ, or you could chuck the .444 trimmer in a drill and file it down to .375", I made a .204 trimmer from a .22-250 trimmer that way. I've made trimmers for a few cartridges that Lee doesn't make them for, just takes a little work.
Tim