Yes, TMPGenc comes with split/join tools. I've only used them with MPEG-1 (VideoCD), so I can't comment on how well they work with MPEG-2.
Also, the newer versions of TMPGenc (12c and 12d) only allow usage of the MPEG-2 encoder for 30 days, after which you have to pay for the program. Something about the licensing fees from the owner of the MPEG-2 patent.
The older TMPGenc 12a will encode in MPEG-2 for as long as you wish, although I was never able to achieve good quality without deinterlacing the video. I guess that wouldn't concern you, though, since Divx is already deinterlaced. 12a should still be available for download
here. You'll have to download the Japanese version, and then apply the English patch.