Fighters are a bit pricey for what your using them for however, it be better to use a anti-missile system. Fighters cost a bit more, espically if your using living pilots that need years of training. Shields can add on to the price.

My idea was to just build a ton of drones out of scrap metal/easy findable cheap metals with a thruster strapped on. They then be released in massive quantities from ships, easily blocking missiles and fire from weaker weapons. A lot cheaper to.