Good find on the Mats Richard. I was going to mention that I have both a Repo set from the 80's and an NOS set of them. Main difference is in the FoMoCo on the originals.
Now, on the License Plate Frames; there are two listed in the January 1967 MPC (first image attached), and then three in the Accessories Section of the 1960-68 MPC, the sheet is dated June 1968 (second image attached). So, as Jeff mentioned, I guess it depends on what was "laying around" as to what was included, as all are correct depending on when the car was built. On the second type that Jeff pictured in the FoMoCo box, back in the late 70's, I too was skeptical of this type being later as I had seen this type on many Fords during the 70's. Then I came across an NOS one in Rotunda packaging with the C7 number (Jeff's box just must be a later issue of the same part).
I agree with Marty that the RPO Protection Group was just a packaging of three already available Accessories.
I have shown also below, pictures of the three different License Plate Frames for your info.
Bob