I've acquired over the years, including a vintage 1960's-era Muncie pattern knob and a Mopar-esque pistol grip, so I switch them up from time to time for some variety.
After seeing your pic of the Hurst Pistol Grip shifter I ran across one in Pep-Boys for a pretty cheap price. It includes a variety of different thread adaptors so it will fit early and late GT500's.
However, I wanted one with a built-in button in it so I went on-line and searched. I found the same exact Hurst Pistol Grip shifter WITH a Line Lock or N2O button built into it for just slightly more than the Pep-Boys price.
Once/IF I get Granatelli Motorsports to straighten out their mess (I got a '09+Earlier unit in a '10+Later box) I'll be putting a Hurst Pistol Grip shifter handle, w/Switch in my GT500 for race days.
Thanks for the idea,