You might approach
Precision Replacement Parts. They're the major supplier of windshield gaskets and lockstrips in North America. The lockstrip they presently supply for their DWG625 (windshield gasket for these cars) doesn't look or fit like the original. They probably won't be too interested if you present this as "Here, let me send you a sample so you can make a more accurate lockstrip for this application you already cover" -- not enough volume for them to pay attention. You might stand a chance if you present it as "I need this exact lockstrip reproduced, here's my sample, I'm willing to pay, the new one has to look like this, and oh by the way this lockstrip will also fit and look much better in the gasket for NAGS DW625 and DW590".