http://www.gowesty.com/Merchant2/merchant.mv?Screen=CTGY&Store_Code=gw&Category_Code=_poptopcolors

or

http://tinyurl.com/yd25jx

They have the best selection that I'm aware of. I have the canvas/gray ....
wishing I had the acrylic burgundy ... because it would be cool ... and my
van would be cuter! (see what kind of flack I get on that one)
I really like mine. Easy to install, use, keep clean. Been in major downpour
rain, top popped, cozy and dry as a bone. And you're right about 3 windows
.. much better circulation, especially when you have both hatch and sliding
door opening screens. A very well-vented set up when it's warm out

Van-cafe also carries both canvas and acrylic, but not sure about colors.
Eurocampers doesn't appear to have canvas replacements, but sure does have a
bunch of other stuff....

Happy shoppin' Matthew....

Bob Stevens
'87 Westy Syncro
"Passion Fruit"