Hi swym_staff,
We do have the capability of making custom battery packs, so we might be able to produce what you need. Please take a look at the following link for how to inquire further about this:
One other possibility: we do sell some battery holders from Keystone Electronics which have isolated solder tabs for each cell, which allows one to wire in any fashion they choose. Here are a couple of options:
Additionally, they also have the capability to make customized holders. Perhaps they could work with you for a solution.