I took a pic of the VIN on a 2016 331 and went to dealer and ordered the lever assembly and the screen for that trailer and removed the clip style latches and modified the frame with a grinder. Works perfect I am currently ordering the other side fixed window that is 22x12 with one that slides up and has a screen at the bottom. I have ordered it at
www.Trekwood.com. it was under $200.00 with shipping. It will be a framed window not a frameless but it will open then I can finally have cross flow ventilation in my bedroom. I noticed a 2017 that had that same window while traveling in Las Vegas and it was hardly noticeable.