Should I get a wall plug in battery charger or new battery?

My 98 BMW 740iL battery went dead. The battery crank was weak for last couple weeks.
I am retired, no daily commute and do not drive as often. Typically couples times around few mile per weeks around town.

Garage battery meter test result:
Volts 12.32V
Measured 585 CCA
Rating 950 CCA
Starter Test 10.23V
Charging Test 13.99V

The current battery was replacement in 2004 Douglas Battery PS95R-675.