Beat me, Keith.
Most people seem to prefer Polarguard 3D to Primaloft for stuff like sleeping bags, quilts, etc. It's a bit lighter and is more of a sheet and doesn't need a ton of quilting.
The only place I know of that's currently selling it is Owfinc. They don't print the brand name on the site, but it's listed as PCF63F. It's about $11 a yard for orders under 20 yards and $8.55 if you get 20 or more yards.
It's a fun project that shouldn't take more than a few nights.
Most importantly, don't forget to post pictures.
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