Cowl Replacement

[240sxProject2006]

I need some help. Got my 240 about a month ago, and the building process is getting more and more expencive each day. I live in Hawaii, so in order for the car to be registered and legal to drive on the road, it must pass a safty inspection. Part of that inspection is the Windsheild Whiper Assembly, and thus brings me to my Question. The entire Cowl of the car is rusted out, and the Assembly cannot mount to the car. Ive been told this happens allot with this car, and is very expencive to fix. I got one off the wall quote for 1500 bucks to fix it. How much should I pay, and would it be best just to get another car? Any Input would be greatly appriciated. Thank you