You're just going to have to get used to going to 10 different sites. Marco has a lot of good game specific parts. So does PPS, Pinbits, little shop of games,..... you really can't one stop shop and some parts are cheaper on one site but another part is cheaper elsewhere and the parts are in limited supply everywhere. I think it's part of the fun of pinball repair, personally.
I wish there was a better answer but there isn't.