If you are speaking of having only a pistol grip & not a stock, the answer is NO. If you wish to add a pistol grip & have the stock on at the same time, the answer is maybe, it is a matter of how much gunsmithing you wish to pay for. In general, a good gunsmith can do anything if you have the money and it is legal.
lcj
You cannot purchase a pistol grip for Hatsan/Escort shotguns. It is illegal to sell/buy pistol grips for any shotgun mfg. outside of the United States.
chuck Norris
Yes
A pistol grip shotgun, according to the ATF, is rulled as "any other firearm" and the buyer must be 21 or older to purchse..
No
The first known pistol grip shotgun is called a backpacker shotgun, with a shorter barrel, and shorter overall length. This is a very popular version of the shotgun, mostly purchased for home defense.
20 and up
100-400 or so
custom proposition
Never?
About $285 at Gunsatcost.com
Unlikely