If you have the time and space, Tim, I recommend making all your own strapping. It is not that hard to do as long as you have the right equipment, which can be purchased at Lowe's (soldering iron), snap setting tool (Michaels) and nylon/elastic/Tandy snaps (Joannes fabrics or eBay).
Imperial Boots has two different types of strapping kits available, the EZ kit and the TK ("Classic") system. The EZ kit connects things with Velcro. Not recommended. With the other, the brackets are screen accurate but you will still need to make your own strapping for other areas besides the torso anyway.
Being as you are building two kits at once, you will probably be better off ordering/buying the nylon, elastic and such in bulk.
I have a link to a tutorial under my avatar below that can help, and if you have any questions, just let us know!