Funny you would ask after all this time.
The original sticker price was $380 for factory Hurst shifter on 2010. My car was an early order from October of 2008 and it had that option selected. The car build was put on hold because the shifter option was not ready for production so the other choice was to pull that option off the order so the car could be built.
I purchased a lightly used take-off Hurst later and installed it myself but used a MGW Race knob because I dislike the big baseball that comes from the factory. Best of both worlds. This one is retained by a set screw and feels great in your hand.
The early factory shift knobs were press fit so yours should not spin at all. If you can't smack it down tight by hand, something is wrong. The knob may be damaged/loose.