I guess its all dependant on what you feel comfortable with. I live in MN too so I know all about road salt, but you are still able to find decent trucks from the 80's and 90's here.
If you wanted a chevy I agree with the others and saying a 73-87 or even newer with a 350 or 454 would work out well. I'd probably stay away from the 305.
If you wanted to go with a ford (body style changes of 73-79, 80-86, 87-91 or 92-96) would probably work also. As for personal visual preference I l like the 73-79 and the 92-96 body styles the best. Motor choices of a 300-6 (4.6L), 351 or 400m (70's), 390 (70's) 351w (later fords), or the 460. I'd personally shy away from the 5.0L and probably the mazda 5 spd transmission found in the 92-96 fords and also the 360's found in early 70's fords. I own or have owned 4 5.0's in trucks: a 93 5.0 (speed density), two 94 5.0's (mass air), and one 97 5.0 (mass air with the GT40 heads). The only one I've been impressed with as far as power is the 97 and thats in an exploder. I'm a huge fan of the 300-6's in terms of longevity, torque, gas mileage, etc., but they definately aren't speed demons
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I'm not all that familiar with dodges so I don't know have much information to offer except that if your not going to have many body styles to choose from in your price range. Didn't they have just one body style from like the 60's up until like 94
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I don't think your going to find anything diesel or with a v10 in your pricerange that isn't going to have a ton of miles on it and isn't on the verge of needing a lot of money thrown into it.