You probably won't find just the lense.
Try your favorite RV parts store, it called "Thor Acron light"
Here's the whole thing, $20 on amazon.
https://www.amazon.com/Thor-Acorn-Li...1783350&sr=8-1
Cheaper here.
https://www.vapapgh.com/index.php?ma...ucts_id=180721
Thanks for reminding me, ours has a burnt out bulb
replaced it.