Quoted from CactusJack:Oddly enough, the production numbers are missing for a lot of the WMS games of that same era but had some really big hits too (4000-5000 for a few titles).
I've sent all those numbers to Jay, but I also sent him a lot of other stuff too so it may be a while before he gets them all into the IPDB. It's 2xxx-3xxx for most replay titles, couple of hundred for most AAB titles, then as you say the occasional bigger hit.