Try mad amusements in the USA. they have brand new replacement LED displays and are very affordable/well priced.
Otherwise, jeff from classic arcades in the USA is also worth a look as he often has refurbished 2nd hand or NOS stuff, otherwise Marco Spec in the USA is always worth a look.
I have bought from all 3 companies many times with great results. hope it helps.
If you are looking for one of the LED displays, Greg from RTBB is the sole Australian distributor. I would check with him prior to purchasing one overseas.