Scaling Single pages

Select measures and increase or decrease layout stretch (shortcuts or menu Format/Stretch).
https://musescore.org/en/handbook/4/systems-and-horizontal-spacing#layo…
https://musescore.org/en/handbook/4/user-interface#main-menu

"I tried using the scaling on the Page Settings tab, but I can't find it for individual pages."

The Scaling set through the Page Settings tab applies to the entire score. You cannot set a Scaling value for an individual page within your score. So you have a choice:
a) either create separate scores for those images which you need at a defined Scaling (small, normal, large)
b) or use screen capture for each individual image, then reduce or enlarge each image as needed

In passing, I would point out that the definitive music notation textbook "Behind Bars" by Elaine Gould (publisher: Faber Music Ltd) has hundreds of music notation examples. And almost all examples use the same scaling (except for illustrations of ensemble and full orchestra scores).

It's not clear why you'd want to do this = an example would help - but one method might be to use different staves and set their scaling individually, an d set them to hide when empty.