Every SKU is assigned a unique identification number (inventory or stock number) which is often the same as (or is tied to) the item's EAN or UPC. SKUs may be a universal number such as a UPC code or supplier part number or may be a unique identifier used by a specific a store or online retailer. Many retailers use their own SKU numbers to label products so they can track their inventory using their own custom database system.
You may want to check with a company like Paxar / Avery Dennison. They provide price tickets and hangtags that utilize UPC's / SKU's. They may be able to help point you in the proper direction.
I have never used this software, but the following software may be some help to you. Simms Software : The SKU Configurator can be used to determine the composition of the SKU number. Selection of some characters from the item's category, subcategory, vendor's part number, manufacturer or vendor will add them to the SKU number's format. Users can instead choose that an auto-generated number to be part of the SKU.