It’s a commercial product that actually doesn’t have lethal effects of its own. this isn’t something like a Stinger Missilehow would the USA allow to export those to PAP/PLA? (most likely PAP)
People use it for varmint hunting. As such export controls are light. Even if the US did block sale to the mainland most of the controls are nonexistent vs Hong Kong.
your Mini DMR runs into the major issue of the sight it’s self. The HAMR was designed for a 5.56NATO ammo type. Now you probably wouldn’t have much of an issue if you used it with 5.8x42mm or 5.45x39mmObviously you don’t want your whole SWAT team so equipped, but having one member in the team with this mini-DMR setup would make sense in my view. It would certainly be much safer and user friendly then the typical 556/5.8 combat rifles I regularly see at airports and city centres (western nations only) world wide.
But 5.8x28mm or 9x19mm even the old 7.62x17mm is a very different trajectory and drop. You would need to change the reticle set for the 4x power scope and make adjustments to the Delta point. It just doesn’t make a lot of sense on a SMG. A Rifle has a flatter trajectory these were made to compete against ACOG on M4.