I'm afraid 40 cm is the biggest you are going to find. Lysiosquillina maculata, Harpiosquilla, and Bathysquilla all push this limit, but I have never seen a stomatopod over 40 cm.
I suspect that it is physically impossible for an Odontodactylus scyllarus to reach 53 cm. At that size, the raptorial appendages would probably self-destruct if it struck. I'm afraid O. scyllarus just don't get much over 18 cm.
Roy