Since I really admired the long-lasting
Panasonic 105D31L-MF battery that came with this 2005 SR5, I was hoping to find an exact replacement. Unfortunately, they aren't sold retail (or in the US, from what I can tell).
The Panasonic 105D31L-MF battery seems to be a 'cold climate' option, larger than most replacements. It's dimensions exactly match battery group size 27 here in the USA.
I plan to replace it with a group size 27 battery, which should have comparable CCA and reserve power, or at least match the 755 CCA and 165m reserve on the Panasonic 105D31L-MF. This 4Runner has roamed the mountains of northern Nevada for over 13 years with a sealed lead acid battery, so I see no reason to pay more for an AGM variant.
EDIT: I purchased a
Duracell Ultra Gold SLI27FM battery with 710 CCA for $130.