That would have been a great idea and it turns out that after a bit iof searching on this forum I should have been warned since there are many examples of this happening, even on Kiotis.
I just bought an orbital AGM battery made by exide, a starting battery with 1000 CCA, black just like yours TBDonnely but a newer model, for a whoppin 111$ at Napa about 5 minutes ago. I am glad to see it will fit in the hole and the wires will reach though I was pretty confident. Too bad the terminals are switched, the battery will have to sit in their backwards with the label facing the radiatior.
The Napa guy charged me a 5$ core charge and says he will take all 14 of the batteries I have found on my property. I will keep the walmart battery for a backup after I check the acid levels.
The "OEM" battery only had 720 CCA while this one with 1000 CCA at 32 should give me great performance.