5/8 inch channel balance repair kit.
Commonly used on glass filled nylon guides by many manufacturers.

Contents:
x2 Top Guides
x2 Bottom Guides
x4 Rivets
x2 Take Out Clips

Related Parts:
60007 - 1/2 Inch Channel Balance (5/8 wide x 9/16 deep) w/shoes non-tilt

Priced and as a package.
Please check measurements carefully to ensure a proper repair (see 2nd image).