Hi; Welcome to the forum. There have been a number of owners here on the forum parting out HiLos. Do a search here and see if you can find one. another idea would be to see if any of the bedroom windows that are emergency exits might fit in place of one of your windows. If you were lucky to find one you might fill in the old escape hatch opening with a fantastic fan. You might call JandR trailer repair and see if Jim or Rob have any ideas.Their ph# is 740-392-1600 or 1602 .
Jim L & Faye
2003 Silvarado diesel crew cab
2017 Silvarado, crew cab 1500 6.2L gas w/ 8 speed tranny