Hi, doesn't sound like what you are after, but CPC make a repro of the 68-73 cover, with the correct markings etc. It is not the same as the cover offered by Scott Drake, which is a nice aftermarket unit, but not a reproduction of an original.
I don't have a 67-73 repro in stock, but I do have the Repro 64-67, and it is quite nice. I also carry aftermarket ones, if anyone else is interested.
I will have a repro 68 onwards one on my next order.