i typically do my own so i cant offer any advice on that. i have had excellent results letting mine cure for 30 days before reassembling and use. far better results than assembling shortly thereafter. the longer it sits - the harder the finish gets.
Try CCR Refinishing. I have had them do their Cera Plate on my Glocks and a XDM Barrel and their work has been awesome. Website address is Cummings Custom Refinishing