I bought these from Cabelas:
Link.
I found my old order, still the same product. They were $12.99 in July of 2011 when I bought mine, now they are 16.99. That's > 9% inflation. :R :W
Still a great price. We use them every time out for 3 years now, and they are holding up well. Had to buy 3: one covered the rear bunk perfectly, and we stitched two together for the front bunk. They are held in place by maybe 12-15 mini spring clamps that I bought at Home Depot.
Mini Spring Clamp Link They hold even in VERY high winds. Camped at a Columbia river site last year where our neighbors Motorhomes awning was folded back onto his roof, and picnic supplies flew by horizontally on a regular basis. Even a tent crossed our site on it's way into the river, LOL. But our blankets stayed on tight - almost unbelievable. :C