here are a few early career exemplars for your reference:
1969 puerto ricanleague contract:
https://m.ebay.com/itm/EARLY-69-70-T...-/362065669711
Take a look at the 1969 govt postcard:
https://www.psacard.com/autographfac...rman-munson/35
1968 Binghamton ball (note also the Fiskland signature)
https://m.ebay.com/itm/1968-Binghamt...915?_mwBanner=
Cool piece!