The 285 hp motor was the most common in the 92 and 93 models. The stock (250 hp motor) has the benefit of coming standard with a 4160 carb instead of the 4110 that was so problematic and often replaced. I'd rather buy a 351 and add GT40p heads than swap the carb. Cheaper. After that, the horsepower is the same or better since you should probably put an intake in as well at that point.
As for the brakes, its probably in need of a new actuator (guts) and new brake lines. Probably $400-$500 as mentioned. Deals and vinyl will be reproduction. Probably not huge money if it's just in a couple of spots. I'll split the difference at $9,000 on the high end without seeing pictures.
Previous: 1993 Prostar 205
Red 1998 Ski Nautique, PCM GT40, 310 hp, , Acme 4 blade, Perfect Pass SG/Zbox.
Be kind. Have fun.