Hi, Simos!
I second Al, they look like US cavalry from 1876 to 1900. We adopted a more Prussian style of dress uniform, in the wake of the German victory in the Franco-Prussian war.
Regarding collecting bands, yeah, some guys do. There's a gentleman up in Canada who specializes in bands, both collecting them and producing sets, Bill the Bandman is his handle.
I think we even had a term for collecting to a theme like this-a cameo collection.
Whoever this guy was, who produced the estate pieces you're sharing with us, looks like he was prolific, and he did a nice job of capturing the classic toy soldier look.
Thanks for sharing all of these, keep 'em coming!
Prost!
Brad