Could you do tarballs or zip files, rather than rar files? They're much easier to deal with than recent rars using free software (the only program I know that will do it is unar[0], which depends on loads of GNUstep stuff). 0. http://wakaba.c3.cx/s/apps/unarchiver.html
Disrupting the originals inhibits verification with others who possess mailings and should be avoided. Supplementation is fine. There's this if you don't mind blobs. http://www.rarlab.com/download.htm RAR is proprietary. ZIP is not compact. Assuming Cryptome's working platform is not an opensource Unix, I'd definitely consider switching to 7z, which works on or is shipped with Linux/Win/BSD/Mac, is opensource, and produces great compression ratios. xz is another fine choice. There are probably prettier GUI's for lzma/lzma2 out there if desired. http://www.7-zip.org/download.html http://tukaani.org/xz/ 917504 1.xz lzma2 1718180 1.7z lzma 1873481 1.rar proprietary 2247179 1.bz2 b-w-huff 3341315 1.gz lz 3345104 1.zip lz 13323604 1.tar (wget src)