I get the almost exact fit battery from this seller on ebay:
http://www.ebay.com/itm/New-NOS-Wisc...60969948079%26
This seller also has a good selection of replacement parts for the old Honda's.
The parts lists and manuals may be found on ebay, or perhaps another member has a link for a download. I sold my copies a couple of bikes ago and all I have left is a microfische parts list.
Check my albums under one of my CA160 titles. I have some copies of CA160 parts and a partial owners manual.