Reddit reviews Oxford Poly Index Card Binder, 3 x 5 Inches, Color Will Vary, Includes 50 Pre-Punched Cards (73569) (2 Pack) …
We found 1 Reddit comments about Oxford Poly Index Card Binder, 3 x 5 Inches, Color Will Vary, Includes 50 Pre-Punched Cards (73569) (2 Pack) …. Here are the top ones, ranked by their Reddit score.
I have a friend who uses these. She loves them, but I know they're a little on the expensive side.
https://www.amazon.com/dp/B07F24KN8N/ref=twister_B07L8P6CXY?_encoding=UTF8&psc=1
Additionally, you could punch one hole in each corner and loop 50 on one binder ring then those on a larger binder ring.