I don't think a lot of pinball people realize that specialty pinball parts are more often than not made by individuals as a side gig, and then sold to places like Marco who distributes them the masses. It is a great system, and Marco is an awesome company to work with. BUT, we as consumers are at the mercy of those individuals being able to meet demand and make parts. The little guys are last in line for materials from the big suppliers. There are people out there making parts who are quite old, and age is eventually going to catch up with them. There are a couple small part manufacturers I have heard of where the sole person doing the manufacturing is around 90 years old. Sometimes people have other issues in life, and making those spare parts as a side gig has to be put on the back burner.
I can tell you right now from making ramps, that Pinball part demand is huge right now, and has been for the last year. I work my day job for 9 hours a day and come home and put another 4-5 hours in every night and a 8-10 hour day on Saturday most weeks. I still can't keep up. I worked this schedule for about 4.5 months straight earlier this year before taking a break, and I am barely able to build stock up. After Pinfest, I am probably not going to be doing any production in September-October, only shipping what I have on hand. So if you see something...don't wait around- buy it when its available, because you may be waiting a bit until it comes back into stock.