IMEI on i9300 with 4.4.x rom

Hi guys, sorry if this has been asked before, I’ve been searching for hours trying to solve this problem.
Is it possible to use a 4.4.x rom on a i9300 and repair the IMEI?
I’ve tried almost everything I can think of and several different roms but no IMEI, z3x says it has repaired it but it still doesn’t work.
Thanks in advance for any help.