I heard back from one of the 4/5 auction houses I sent pictures to.
They were under the impression that these are from the early 1900's for the Italian infantry officer. More specifically, for a second lieutenant's (sublieutenant/ sottotenente) parade wear. They said the "Unione Militare Napoli" is the trade seller's mark/signature and are fairly common.
It's interesting, I have searched all over using Italian terms (spaline/sottenente/etc...) and have come across only a couple other examples. So, if these are so common, maybe they are as common as chewing gum, and people aren't selling them at auction or on websites such as eBay, or maybe they meant common as in lower rank officer, and only the higher ranked officers are less common.
Either way, they are a cool piece over 100 years old, and I probably will leave them un-polished and try to sell them eventually, or polish them up and keep them as a conversation piece.