Seems like the code of c-repl can now be found at a Github repository. It seems to be a dead project, though (last commit was 3 years ago), so I'd suggest looking into alternatives as well:
- CINT Archived old official page from web.archive.org or "Masaharu Goto" CINT page
- ccons Github or code.google
- Cling, successor of CINT, but only supports C++ (which might or might not be a problem, depending on what features you need)
