Smith and Alexander are producing a lot of special parts for the M-1911 pistol. One that is especially useful is a south-paw magazine release button, shown here. It can be used to create a 1911 for lefties (left-hand shooters).

They also produce a similar part for Para Ordnance guns.

Finally, they also produce several kind of magazine wells for both single-stack M-1911s and Para Ordnance, as well as grip safeties. See pictures below.