According to SAKWiki, the Spartan’s predecessor without keyring, toothpick, or tweezers was called the Standard. https://www.sakwiki.com/tiki-index.php?page=Spartan#History.com/tiki-index.php?page=Spartan#History
Closeup stills would be easier for me to see. Late ‘80s to early ‘90s would be my broad estimate. Parts are from late ‘80s (opener backspring) but advertising knives are likely using parts being disposed of in my estimation early ‘90s.