With time and patience, you could at least fabricate the armor itself using sintra plastic (technical name for it is "foamed PVC" ) I prefer 1/8" thick. I've been able to get a 4'x8' sheet for around $35 in the past. Rub and buff silver leaf at micheals (or online) is only a couple bucks. You could then probably modify some coveralls to make the flight suit. Gauntlets? Well, that'll be more time consuming and require more patience but could be made from Sinatra too...well actually all of the other parts technically could be.
Search for "wizardofflight," he's a member here who created various templates for the armor you can use to piece together in varying scales/sizes.
If you want a cheap helmet that doesn't look terrible (shape wise) I'd suggest trying to pick up one of those boba fett helmets that were sold recently (after TFA came out) at Target stores. They're not perfect, but the general shape of it was pretty decent, especially compared to the more expensive, craptacular rubies. IIRC it was about $30 for that. You can use that tube of rub and buff for the silver and the other blue paints aren't that much more expensive either.
As for the flak vest and other leathers, you may need to be more creative with that. I'd encourage you to find someone you know who may be skilled with sewing and see what kind of pleathers/alternatives can work for you