On getting a new front window, I'm not sure about being able to get a new window that has the multi pane crank out opening type, known as an jalousie window.
But here is a place to start. This past winter I ordered a custom made cargo compartment door from Lippert Components. Come to find out most all cargo doors are made custom to order as there are so many sizes just the RV manufacturers orders many at once. The price and lead time of 2 weeks for my 1 door was really not that bad. The cargo door was an exact match to a 2005 Sunline.
It seems they claim they also make custom windows. See here and follow the link to "order replacement windows" https://www.lci1.com/rv-windows
The LCI link then takes you to Duncan systems which most likely is a LCI now owned company. I have never used them, just passing along as I found this when getting my cargo door.
You can also try here for Hehr windows and they seems to show the jalousie window. Creation windows
It seems they are sold through Parkin. I have never bought a window from Parkin but have some other items and had a good experience.
Hope this helps
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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