retroprotection.com has put the most effort into expanding their box sizing options- but honestly, you might be better off checking Ebay. What you're after are the true speciality, one-off size protectors, and those are very tricky to come by. What's available varies based on each seller's customer demand, and sometimes you have to know what games are the same size & buy a protector for something completely different. Ebay gives you the biggest slice of potential sellers, while allowing those sellers to list protectors under each game they fit, so you don't have to do as much legwork.