When was Buck 503 introduced?

[Lightning Boy]

Hello all-

Not having much luck find an answer to my question, so I'm helping one of the resident Buck experts here can help. When was the Buck 503 first introduced?

Thanks in advance!

 

[David Martin]

Boy, Buck brought out their Prince in March 1977. A handsome looking model with polished stainless steel frame, burgundy micarta slabs and 440C blade. Plus, it was given the old English script stamp. This series holds a stylish look. DM

 

[Lightning Boy]

Thanks, David!