Real light Henley shirt

You also might want to perhaps look at ghillie shirts, too. That pirate/scotsman looks pretty Star Wars-y: https://www.amazon.com/PAUL-JONES-Lightweight-Scottish-Jacobite/dp/B076MVQ3LV/ref=asc_df_B076MVQ3LV/

Not sure what pants yet.

For my fighter jock pilot outfit, I'm probably going to go with these guys (in Rebel Orange, to boot!) https://www.amazon.com/CQR-Tactical-Repellent-Ripstop-Lightweight/dp/B08V947K1Q