They shouldn't have a leg to stand on. If the service had been done 2k earlier would the alloys now not be bubbling? No. They should do it, no questions asked.
you'll need hoses disc's and the calipers...Why bother though I find the std JDM calipers more than up to the job , even on the few track sessions I have done just upgrade the brake fluid and pads
Why would you need discs? Are they diferent sizes?