80's Granby escape window replacement

[algiordino]

Hey folks, doing an 80's Granby rebuild. Unfortunately I'm missing half of my 18"x66" escape window. Located in NM near the four corners, was hoping someone could point me in the right direction for a replacement candidate. Photo with the measuring tape is the pane that someone threw the frame away from and replaced with a piece of plexi. Other window is a swing out that works well.

Checked with five star RV salvage, no dice sadly. Any thoughts? Seems like a strange window size.

 

[BBZ]

I got all I needed at 5 star.. however, I had to dig through piles of stuff to find what I needed.. they say they don't have it, but I doubt anyone went out to the yard to look around..