Built the cover for my -7 from a giant truck cover that I bought from Amazon. Silver waterproof material with a soft fleecy liner. You can get the one for the biggest crew cab long bed truck made (your choice of brand) for about $80. Truck covers have a ton of bit flat places that take a lot of material. It would easily make 4 or 5 canopy covers.
I tacked the rough cut pieces on inside out and clipped it together with binder clips, then trimmed it and double sewed all the seams. Straps around the edge and tie downs under the belly and nose. It's non stop waterproof and snug so no movement in a breeze. Did fine at Oshkosh this year, including the big blow on Saturday.
The machine I used is a walking foot, and that did a great job, but a lighter machine would probably do just fine.
Another DIY for your DIY plane.
Cheers