Look for a Ute Canopy mfg.
They fit all types.
Caravan builders, repairers.
Any reputable Handyman.
Yourself.
Cardboard Template. mark around it, Cut and seal with epoxy.
Offer up window. Mark and drill bolt/screw holes.
Adhesive round hole.
Install frame and fix bolts.
Shake hands with yourself.
"Job well done". then go indoors and have a nice single Malt to celebrate.
Just don't tell missus though.
She'll find all sorts for you to do after that.
Yea. Second thoughts.
Pay somebody. "I'm useless it those things love. Honest"
Little Chuckle.