I agree with "Teach Peace" before spending any money spend a weekend checking the each of the original components on the car; Remove each caliper and verify that each piston is free, flush the brake system and replace with fresh Dot 3~4 brake fluid, bleed the system at least twice or until you get a firm pedal and then perform some test in a safe manner. I had simular concerns with my high performance brakes on my Pantera and did the above and found that several of the pistons had frozen up in the calipers.
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