problem with the frames, need some advices please..

[rhmeed]

Hey everyone, I was stopped by the cop lately driving my 86. The reason why I was pulled over was because the car wasn't safe to drive, when I checked on the mechanic, under the car is entirely rust proof, and there isn't any signs of rust, except the frame that is holding the car is completely rusted. When I asked how much, he said to fix the frame your gonna have to spend at least 5000 dollars Canadian, which is a lot. i dunno if this price is suitable for the fixing, or do you guys think there is a lower price than this, and does anybody know if I can buy frames for my 86, or a way to fix the frames I have?