Free: Contests & Raffles.
Any long sleeve will do. breathable is better. Spray it before hand with Saywer Permethrin. Also spray your pants and hat. That will do a good job keeping the bugs at bay.
Suns out guns out.
I also wear a lightweight synthetic of some kind. I have Under Armor, Kuiu, First Lite, Columbia, etc... all work but none stop bugs on their own. Permethrin works awesome and has become my go-to. I always carry some bug spray for my hat/face/hands/legs, as I can't stand wearing pants when it's hot.
I wear a long sleeve UA shirt quite a bit in the summer. Not sure exactly which model but they are 1/4 zip.