Ryan,
If you were to mount a cooler, it would have to be behind the engine near the flywheel where the fresh cool air is. You can't put it up front as the air up there is hot, plus the fan on that unit you posted a link to would melt up there. Someone here tried something like that already.
There was an oil cooler available for the CH engines, that is just like what I mentioned. I don't have time to look for it right now, but it's out there. I'm not sure if there was one available for the Mag's or not, but it's dooable.
