Yeah, I sort of agree, although that engine number appears a bit higher than I would have expected.
engine number:
2J2-000101 onwards = US model 1978 SR500E
2J2-020101 onwards = US model 1979 SR500F
2J2-100101 onwards = Canada and "Others" model 1978 SR500E
2J2-110101 onwards = Canada and "Others" model 1979 SR500F
("Others" = anywhere outside of USA, Canada, Oceania, Europe and Japan)
2J2-150564??
Seems a bit high... Are you sure that engine number's correct? Not a misplaced digit somwhere?