How about glass fronted shadow boxes. They'd have to be custom, but those skates are works of art and might be worth it.

This isn't very original but you might consider lucite display cases as seen here with shoes.

I would go with a large cabinet type display in the style of an old department or sporting goods store window. It could be dressed with suitable fabrics and old posters or ads on the back wall and done up just like a ski and skate shop would be in Sun Valley Idaho circa 1940's or 50's.

I have a friend who keeps all her beloved shoes on the stair case - a pair on each tread ! admittedly it's not the main house stair case - just the staircase from her bedroom into attic storage room - but it does look lovely !! might work with skates too ( if they aren't too big ?!)