Faded window help

Hi, one of our windows is faded as you can see in the picture, the top right one. We only found the Patent number on the hardware and was not able to confirm the brand of the window. I hope you can help us identify it so we can replace it. We have 2 other ones like that at our house and would like to replace all 3 of them. Please let us know where can we find it so we can order it. Thank you very much!