I sent the following to Jane Tachuk. Others more familiar than I, particularly with the Hurst, may disagree with my thoughts.
I noted your request for valuation assistance on Leo Vanderbyl's 300 Hurst on our Chrysler 300 Club forum, and will offer a tip or two. I am merely a fellow collector interested in the Chrysler 300 "Letter Cars" in general, and the owner of a 1957 300C.
The 300 Hurst was a low production car at a reported quantity of 485 cars, so it is somewhat rare by collector standards. Yet balancing that is the fact that the collector interest in the 1970 Hurst, as compared to other Chrysler 300s dating from 1955 through 1965, is fairly limited. And this mild interest holds its market value quite in check.
There are certain valuation tools - such as Haggerty Insurance Company - whose advice is best taken with a grain salt. Bear in mind that an insurance company will benefit from over-estimating value because its premiums charged and its profit increase more than proportionally along with a higher agreed value. Therefore Haggerty's online valuation of the 300 Hurst - in a range of $20,000 to $56,400 - should not be taken seriously at all.
It would be more productive and accurate for you to search the internet for the 300 Hurst model cars for sale, noting the conditions and the asking prices of these vehicles. Then, with the understanding that virtually all sellers will be willing to lower their price to meet a buyer, take perhaps 10% to 20% off of the observed prices to establish a reasonable private-party buy/sell true value for the car you have.
My personal estimation is that - depending on the actual quality of your particular vehicle - your car's value could be as little as $5000 for a "fair condition but restorable" car, to perhaps as much as $30,000 or $35,000 if it is in absolutely perfect "concours" condition.