It's usually cheaper to buy a new case with the glass included. Those companies get big discounts for bulk orders, and some of it is actually passed on, especially during sales etc. To buy the side panel separately, or have your own glass custom ground is often more than a new case is worth. I was thinking about customizing my FD R5 with a full glass tinted panel, cost for a piece that size with custom drilled holes, $190.(its tempered glass, unless you are perfect and have the right tools for the job, it's not worth cracking the glass to drill that close to the edge)