The 5p2C with 5pNOP colors

This is the first time I notice this stamp, and I doubt I have a second example....although I will look further. The colors are those of the NOP, but the paper is 2C, and luckily, the postmark matches 1949, a year consistent with normal use for the 5p2C.







Here is a reference specimen for the 5pNOP. The colors are the same, but the paper is different.