finally did it using dump and cdbackup tools.

cdbackup and cdrestore are at http://www.muempf.de/ - it's very useful as
it divides on CD's running cdrecord for each, supports multisession
(cdrestore can read from given track) for smaller >0 level backups etc.

it's BSD licenced but unfortunately linux-only - if anyone needs this i
have statically linked linux bins, that can be used on rescue CD/floppies.