The biggest/largest Staked Plate cooler that will physically fit........In your climate you don't have to worry about over cooling.
The Liquid to Liquid cooler in the radiator is very efficient, Air to Liquid are less efficient & have to be a lot larger.
Both the ones you listed look too small, Wouldn't even consider a Tube & Fin style.
The bigest/largest Staked Plate cooler that will physically fit........In your climate you don't have to worry about over cooling.
Why not just replace your 12 year old radiator and ditch the aux. cooler idea? It worked for 12 years and you would also benefit from the improved engine cooling of the new radiator. The replacement radiators for your vehicle are not that expensive.
No, I don't assume he is a fool and who says you have to put an OEM radiator on it? I wouldn't. Someone in the aftermarket makes that radiator for Volvo, I doubt Volvo does. I think you are assuming too much. Let him decide with the suggestions being offered. I offered a possible solution, you offered criticism which won't help anyone.I appreciate your logical construct here, but it also presumes the OP is a fool and can't do the obvious math:
a) He's in Central America,
b) Have you even priced OE Volvo parts in NORTH AMERICA?
I know he's in Panama, and I don't know that at all, but I've spent decent time in Guatemala and Honduras. You can't order up RTV cheaply, much less an OE Volvo rad. Let's presume the OP isn't an idiot, maybe he knows what he's asking...
I point this out since I sometimes define certain mechanical/financial limits and inevitably someone says (effectively) - 'hey Geezs, for just a grand more you can fix it this way - so why are you so cheap?"
Let's try to maybe not do that?