I recently bought a Beretta APX Compact and I would like to know some good adjustable sights for it

I recently sold a Beretta A390ST shotgun, which I acquired in a trade and never did anything more than have a gunsmith disassemble, clean, and inspect it. The guy from whom I got it, insisted it was a "Silver Mallard" edition. My "Blue Book of Gun Values" (37th ed.) describes the Silver...