R152 is known with a couple of perforation varieties.
One is completely imperforate (R152e). Here's an example of a single tied on a check (partial image but the check is complete).
Another type is a vertical pair, imperforate horizontally, on both silk (R152d) and watermarked (R152f) paper. Here's an example of the first one.
But here is what I believe to be a new discovery: a vertical pair, imperforate vertically.
It is on watermarked paper and has original gum. The center stamp has a crease and the bottom stamp has a thin.
Does this appear to be genuine to you? If you owned it, would you submit it for a Philatelic Foundation certificate?