hurst shifter

This statement in their ad would scare me away.

"May Require A Great Deal Of Modification"

It's just the Indy universal shifter.

The Hurst shifter that was made for the Mustang II transmission is no longer in production. It was a bolt on replacement for the original, with shorter throws. The original Hurst part number was 348-7960. There was one of these (NOS) for sale on ebay just a few weeks ago, it may still be available.
Just a bit of extra info about these shifters...
There also was a similar version made for Pinto's, which is not interchangable.
If I recall, the diameter of the base is different, and it screwed into the top of the transmission as oppposed to being bolted in.

I have a Hurst shifter on my stang... but mine is a T5 tranny so I guess thats the difference.