It used to be you could find dedicated product in cans, similar to the canned air, but for the express purpose of evacuating air and replacing with an inert gas. Unfortunately I haven't been able to find any of this. However, Nitrogen should work as well and is available from any medical or welding gas supplier. You'll need to buy or rent a small refillable high pressure tank. Might be overkill but if you use quickly oxidizing chemicals it might be worth it.