The hehr standard glass seal from Vintage trailer supply worked fine for the awning
window in the bathroom of the boler
17 (hehr part number 09-111/ Vintage trailer supply VTS-195). We also needed to replace the nylon friction pad (VTS-348) for the awning
window - the middle part of ours had worn out. We also used Vintage trailer supply's swivel handle for the jalousie and awning windows.
The hehr backframe gasket was out of stock at vintage trailer supply when we ordered (it's back now) so we ordered from vintage trailer gaskets. Unforunately it got stuck in the post office in the City of Industry, CA for over a week, so haven't tried that yet
by the way, the number on our awning window is 0377 h (with a box around it) C