Well, I saw a mod a while ago, for $65, for something like this. The link is now dead though.
This mod is incorporated with the job file. It lets you players learn and collect recipes, collect the required ingredients, then craft the items. As the recipes are linked to the jobs, you can add unique recipes to each job.
I may soon be creating a stand-alone version of this.
It can use an unlimited amount of items, and quantity, and change these into one.
Any questions just ask...
Paypal:
danny_hanson@live.co.ukWill send to the paypal address, unless other wise told about....
Demo coming soon, Screenies coming soon..