03 Stempede s17 canvas

http://bearcreekcanvas.com/Content/Pricing.cfm

They need the existing to copy. Already called. :(

Try canvasreplacements.com

They might say the same thing as Bear Creek though.

Your next step would to try and find who manufactured the tent ends.
Either from someone who also owns a 2003 Stampede or contact Palomino.

On Forest River Forums, a rep for Palomino hybrids is a member there.
He goes by Palomino Pal.
He might be able to help.