This is for future reference only.
A few months after I bought my car, my radiator cracked.
Thus I went out to search for a cheap replacement.
If you search Koyo's website, there is no option for the 5MT LGT, only the 5EAT.
I found out from a few websites that the 08-09 WRX has the same part number as my 05 LGT, thus I assume they are the same and bought one(under $100).
(my supplier said A stands for Aluminum, C for Copper)
One I have is 13091, not Aluminum. Cheap alternate to the aftermarket aluminum radiators that are $300, as Koyo makes great radiators.
Fits in my 2005 LGT 5MT perfectly. No problem.