Are the calipers seized up?
Can't they clean them off and grease the sliders, If they unbolt the caliper bracket they can wire brush and clean them up to reuse. You can buy caliper recon kits and new slide bolts cheap.
moob is right, you can get recon units, cheap, from motor factors. Don't they include the fixing bracket or is that only the oem kits. Go into a local factor, tell them what you need and let them look in their catalogues.
There are a set of used front brakes on the 'bay, cheap, could reuse the parts cleaned up? item number:
251731054399
Good luck.