There is a new gentoo mirror in Latvia, which is maintained by Linux Center of University of Latvia. Address - http://mirrors.linux.edu.lv/gentoo.org/ , ftp://ftp.linux.edu.lv/mirrors/gentoo.org/ . It would nice to include us in mirrors-list...
Would be nice if you could provide us with some details on your hardware as well as how many concurrent users you plan to support. Also, gentoo-portage is different from gentoo-distfiles. gentoo-portage is an rsync mirror, not an ftp/http one. In case you want to provide an rsync mirror as well, you should take a look at http://www.gentoo.org/doc/en/rsync.xml and setup things accordingly.
Timeout, re-open when ready.