Yes—Agfa Scala can still be processed, but probably not in the original Agfa Scala process. It can be developed as standard black-and-white negative film in conventional B&W developers. If you want positive transparencies, there are still reversal options: some photographers use home reversal kits/processes, and labs such as DR5 have offered black-and-white reversal processing for films including Scala. In general, no lab is likely to be running the original Scala process anymore.

As for old Color Reflections mailers, they’re unlikely to be honored now. They were essentially prepaid processing coupons, and those usually don’t remain valid indefinitely—especially if the company no longer handles film processing. Your best bet is to contact Color Reflections directly, but you should assume the mailer has little or no current value.