Welcome, Scott! Congratulations on your first egg trailer!
You could probably build your own screen door similar to the old bi-fold style
Scamp supplied for years. Forum member Norm (Honda03842) built one for his
Scamp, and the design should easily adapt to other trailers. See posts 506-518 in his thread
Preparing a 1991 Scamp 16. If you have questions, I'm pretty sure Norm would respond to a PM.
There are many different types of awnings, attached and freestanding. Most manufacturers supply
case awnings as original equipment. They're available from several manufacturers and tend to be pretty pricey. Alternatives that attach to the trailer include
bag awnings (widely used on tent trailers),
rope-and-pole awnings (common on vintage trailers),
Shady Boy, and perhaps a few others I am forgetting. A Google site search* on "awning" should turn up many old discussions on the advantages and disadvantages of each type.
(*Blue bar under your log-in information, "Search," scroll all the way down to "Site Search/Google," best way to access the treasure chest of old information on this forum.)
Happy camping!