Is this a window stabilizer? Where to get or redo?

[Cudakiller70]

I'm missing both on the drivers side door. Funny though that side shuts and lines up fine. Passenger side, material that rubs against the glass seems hard/brittle. Can I redo the 2 or just get 4 new ones? Have seen some on eBay, but is their a better source? Thanks

[mopardave]

http://www.rosevillemoparts.com/product_info.php/p/window-stabilizer-bracket-1970-71-e-body/products_id/9435