
It's a bit tough without photos, but from what you've indicated the $10 red seal w/ a buffalo might be a series 1901 Legal Tender note. If so, it's called a Bison note and is highly collectable.
The other $10s with red seals are likely to be legal tender notes as well (red seals are typically, but not always, legal tender notes).
The $50 is a National Bank Note as you indicated.
From your short descriptions, all these notes could be worth a few hundred dollars each. Definitely worth taking care of. As far as preserving them goes, I'd recommend that you get some large size mylar currency sleeves and put the notes in those.
Just a STRONG word of caution though. Without photos, my guesses may be way off the mark

There's a
tutorial on uploading photos that may help you post pics.
Edited by BadDog
10/24/2018 6:43 pm