This shift knob "insert" is new OE Mopar and it will fit many different shift knobs from 80's Chrysler manual transmission cars and vans.  However, note that R (Reverse) is located in a different spot than on Shelby/Dodge FWD cars.   
 
That said, if your knob's "insert" is missing, or in very poor condition, this brand new insert would make a nice addition to your car's interior as long as you're ok with the R being in the wrong location on the insert.   Someone pointed out to me that if you really wanted to, you could carefully use some black paint and cover/hide the R if you were so inclined... and 99% of the population wouldn't even notice.
We only have a few of these and once they're gone, they're gone.  Great price for a new insert!