With the new Manager machines in RP, it would be pretty easy. Just tell a manager to keep exactly the materials required for one (or more if you'd like) recipies of whatever in an adjacent chest. It will automatically pull from other managers on the network to fill its own inventory. So if you either take the items out of the chest manually or they are otherwise removed (pipes, loaders, etc), the manager will try to replace them.
edit: Just threw this together.
Input chest is at the bottom of the image. Three retrievers pull out a stack each every pulse, so three stacks at a time. Managers only accept the items that are specified in its GUI. The chest on the right has no manager- it is for unsorted items or overflow.
This setup was entirely possible with RP before Managers were introduced, just substitute Sorting Machines in place of the Managers. Same basic functionality. However, Managers allow items to go both ways.. so for example, you could keep your project tables stocked with a stack's worth of recipes at all times. Just put a Manager on it with the items you want to keep stocked and make sure to give it a higher priority than your storage Managers and it will keep itself stocked. Once RP is included in the FTB pack, attach a Manager to an Interdimensional Barrel and give it a priority of 0. Give the corresponding chest a priority of 1. Now you've got a nearly infinite overflow storage that will refill the chest as needed. (
edit: Just tried this.. apparently Managers set to "pull all" won't pull from each other, even with proper priorities. Solution: Keep your "top", main storage chest stocked with X stacks of an item. When it exceeds this, the rest go to the matching lower priority chest. When the main chest no longer has X stacks, it pulls from overflow.)
The only downside to this particular system is the noise from the timer. Setting the timer as low as it goes to pull out items as quickly as possible, it makes a lot of noise. You could move the timer deeper underground, or do a repeater clock, or use BC conditional gates. Or skip that entirely and attach the Sorting Machine(s) directly to the chest and set them to pull everything automatically. Plenty of workarounds.