never did that before, but somehow I can't copy or install custom bundles from Sandbox to PROD. Could it be some bugs at Netsuite side? I even made this bundle available as public but still I cant find it when searching in PROD account.

IIRC you have to do Advanced Search on the Suitebundler search for bundles screen and specify your account + the fact it's a Sandbox. I think even putting in the bundle # in the 'regular' search won't work.