IMO, there are no exact copies or replicas.
The Kirkham's (and Shelby's by extension) are on record that they designed their body with subtle cues that vary from an original 1960's Cobra. They designed and built them that way for a reason, so they would never be confused with an original. Also, the Kirkham alloy body is .059" thick whereas the original is/was .050" thick. These are just the basics.
Even the latest turnkey recreations, from Shelby, called "Competition Cobras," from Denbeste, Drew Serb & Kirkham, while close with all sorts of NOS and reproduction parts won't be exact copies. These are the facts and they're indisputable.
The knowledgable and experts of the marque will be able to tell the difference. Schmucks like me? Not so much.
Back to Cobra engines. Cammer all the way!