Try this site: http://www.cobra.com/support/product-manuals.
The radios may work, but see my last comment. No offense, I am also a senior and no way am I giving more than my time, out of good will. 800 numbers cost me money to operate. I answer questions as a hobby, when I have time. Your radios are on the cheaper side, even for GMRS and are worth -0- if they need repair. They would make an excellent intercom. Charging bases, my opinion, just buy new radios. The cost of a new charger and battery will be close or exceed the cost of NEW radios.