There is basically only Precision Rubber Products and Steele Rubber making the gaskets for the 67 to 76 A-Body applications. So all of the vendors are buying from one of the two. Most vendors will offer the Precision line as they are generally half or more the price of a Steele gasket for the same application. Also, Steele rubber has a very small network of vendors as they want to keep the pricing in line with their suggested retail.
We have sold hundreds of the 690 gaskets over the years and I do not recall ever having anyone claiming an issue with one. Having been involved in the manufacturing, wholesaling and retailing these gaskets for close to 30 years, everybody buys from each other to have coverage.
If you want to purchase a specific brand and your vendor is not able to tell you the manufacturer, I would look at another vendor. In this case, search out your preferred vendor for the Precision WCRD 690 gasket. The 690A gasket is the convertible windshield gasket and the 690B is the 67 specific gasket with the lock strip which is only manufactured by Precision with the correct lock strip.
Hope that this helps with any confusion.
Richard
