I recently purchased replacement cases for my FOBs. I believe from Amazon but maybe eBay. Either way two for $10. The only thing wrong with my originals was the red panic button distergarated. I used an exacto knife and plucked the remaining outer ring of the panc button off and realized it was so easy. I used the exacto to pluck the button cover from the replacements and popped them in my original FOBs. Easy peasy.
When I bought the car, the seller stated that the Chrysler emblem on the back covers a MB emblem. Not true. The seller either removed it or the glue failed. I just super glued it back on.
My FOBs are good as new. No need to destroy them changing PCB and RFID chip to new cases. Anyone need two FOB cases minus red panic buttons?