If you're looking for a small battery I'd suggest Lithium batteries. One of the regular posters (herrhelmet) on this forum sells one that I have bought and been very happy with. Website is here: http://shop.testsycl.com/SYCL-CHARGE...HARBALA001.htm
. He offers discounts to Inmates.
I put the 8 cell one into my R75/5. Less than 1/2 the size and weight of the gel battery it replaced with greater CCA.