What's the diameter of the central hole? Checking if it's 4,5, or 6mm will help a lot in identifying which type of spool it is.
Could be made by some ribbon company like Alpad who sold Olivetti compatible ribbons/spools.
6mm diameter center holes on spools are indicative of a Gr4 typewriter spool.
via u/Koponewt at https://www.reddit.com/r/typewriters/comments/1qcocn1/does_anyone_recognise_this_spool/