I know that local harware stores sell those rare earth magnets, you would need to use a bunch to acheive that length but it would work, but I recently found out that the little spacer for the
xtar charger also screw into a pila charger, I am using them in my pila charger as we speak. You can find them at supertmanufacturing.com or ebay also has them I think. At supert, they are listed under the
xtar WP6 II Six Channel Intelligent Charger for .49 cent each, two spacer equal one pila spacer, so in order to charge 2 16340 batts at the same time you would need 4. Good luck.