First thing I always wonder with these threads is: What is your ownership intent?
If you're looking for a truck with long term ownership in mind, I'd stay away from a rusty truck, especially given your location. Sure you can spray woolwax, FF, etc and slow it down, but that's time and money...
If you're just looking for a truck to use and abuse without long term goals then go for it.
As someone who has wrenched on many a rusty vehicle, I've reached a point where paying a minor premium for a clean vehicle is well worth it. It's no fun dealing with corroded and broken hardware. And if you pay a mechanic, labor rates are such that any money saved by buying a rusty vehicle will be quickly eaten up by added labor expenses.
All that being said, I've seen way worse examples than what you posted.