Anti Rust Agent On a strict budget
Citric acid (dry, found at food stores - I get mine at the "asian market" as I have not spotted it at the normal supermarket) is actually a lot cheaper than lemon juice (or vinegar) (when mixed with water to an equivalent strength, or even quite a bit stronger) and fairly good at removing rust without eating the steel after that (I know antique tool users who mostly use it now, rather than electrolysis, which used to be all the rage.)

Rinse, dry quickly (or they rust again immediately) and coat with oil or wax (to slow re-rusting by displacing moisture.) Rinsing with very hot water will help with the drying step to some extent.