I bought them at the Don-Wes Flea Market in Donna, Texas. This flea market has a lot of shops that cater to RVers since there are about 70,000 of us down in the Rio Grande Valley during the winter. The website below should give you a good approximation of the price you should pay and also has another decent picture of the bows installed. If interested in purchasing I would call the phone number that is shown on picture 3. Camping World offers something a little bit different and much pricier.
Hope some of this helps.
The winds in the valley today were a steady 25 to 30 mph with gusts near 40 and we had no problems with our awning installed as it is. We also have full screens around the entire awning area to provide shade and knock down the wind on days like today.