Lots of '67-'68's came with them, but they are neat. My fastback had them, but when I put all the Shelby fiberglass on, I couldn't use them so I stripped all the turn signal stuff off of the otherwise junk hood , including the wiring and got around $200 for it on ebay.
Now that I think of it, the only '67-'68 I can remember without a signal hood is my buddies ratty '67 convert. It's an A-code, four speed car that he's going to re-do "someday". Sound familiar?