Looks like it has had a hard life. New ones are only £30 delivered if it's what it looks like. No point getting annoyed at TIG welding oily alloy and then finding the distorted end leaks for that money.
Dunno what the history of the car that had the oil cooler was, but wise people don't use second hand oil coolers: you never know what they have in them and they're impossible to clean inside properly.
That doesn't apply to most aftermarket water/oil coolers.
Tell me about it
I got it for nothing, thought it may be repairable but Fingers has got me thinking twice about fixing it. Although it is a genuine Mocal which retail around £70. Might try some duraweld rods and sell it on, after giving it a good wash.
I don't hold with the 'contamination' argument. Oil coolers fitted to bikes tend to come before the filter and thus get 'contaminated' with clutch debris etc. Doesn't seem to do much harm. A quick flush-out with a powerful degreaser would get rid of any crap resting in there.
I'd have to pull out my books and think about it, but I'm pretty sure that in cars it's the other way round.
On a bike I'd worry about debris from the gearbox rather than the clutch.
I'd be almost as worried about degreaser residue contaminating my oil, even so, I doubt that it would completely clean out the matrix.
Pick up any book on engine tuning -- I like the A Graham Bell ones, bwth, and you'll be told to assemble engines in the cleanest conditions you can (and we're talking of household dust), and to bin the cooler from any car which has suffered an engine catastrophe.
The cost of an oil cooler is way less than the cost of a set of bearing shells.........
Actually, on a VW beetle engine, the oilcooler costs more than all the bearings in the machine, but if you factor in remachining of the case and crank then replacing that oilcooler still looks like a good idea.