Sold each, priced each

1-1/4 inch steel ball bearing roller assembly
Adjustable steel housing assembly
Inner and outer housing is held together with a flush pin (not a rivet)
Used by Superlite Mfg
Housing dimensions: thickness, 9/16 inch; length, 1-9/16 inch; height, 1-1/18 inch.

Diameter: 1-1/4-inch
Housing Tab Style: F-Tab
Housing Width: 9/16-inch
Material: Steel
Roller Diameter: 1-1/4-inch
Roller Edge Type: Concave
Roller Material: Steel
Roller Width: 5/16-inch
Type: Concave
Width: 9/16-inch

Helpful Article: How to Replace Rollers in an Aluminum Sliding Glass Door