They pop up on eBay regularly and are offered by a number of online sellers.
You can usually buy them from about $50 to a little less than $100. Check out the actual prices at Google Shopping.
However, rare and vintage Shark Tooth knives especially in mint condition can go as high as $300. For prices, here's a link to an eBay page.
Manufactured by W.R. Case & Sons Cutlery Company, which has now more than 2,000 Authorized Dealer locations throughout the United States, Shark Tooth knife was first conceived and produced in 1972, however it was not released to the market at the time.
The age of your Shark Tooth can be identified through block style lettering and the dots at the tang. The stamps used from 1970-1979 are the same as those used between 1965-1969 except that dots were added below the U.S.A.
10 dots were added in 1970, and for every year thereafter, one dot was removed so that each year had a unique stamp.
For clarification, note that ten dots appear on 1970 knives, nine dots appear in 1971 knives, eight on 1972 knives, and so on.
Refer to AllAboutPocketKnives.com's Case Knife Age Identification for more info.
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