I jumped through the US export license hoops and ordered a OST Glock 19 slide milled for an RMR. Brownells can export the kit (OST slide + OEM internals) as they are listed as the manufacturer whereas the bare slide lists OST as the manufacturer and they are not registered for export. Brownells didn't include the shorter screws required for mounting the RMR so I have to find some somewhere else or just file down the original ones that came with the RMR.
Gallery
http://imgur.com/a/llehW#0





















































