I have Pearson catalogs from 1958 (when they started naming their bows), 1959-60, 1960, 1961, and 1963. The first mention of a Stallion is 1960, but the grip is shaped like the Safari that's coming your way and was only offered in 66" length. The Stallion isn't shown in the 1961 catalog. The Stallion with a grip shaped like yours is in the 1963 catalog. In 1964, Pearson went to the CAT# 710 for the Stallion. I would guess that yours is a '63, maybe a '62 (I don't have a 62 catalog, so I'm not sure). From everything I've read, serial numbers of Pearsons are useless for dating purposes.