Prospective parts car?

I came across a 75 Duster for sale for $500.00 w/ clean title. Seller says it has a complete interior solid floors and trunk. Body has very little damage, just some surface rust. No front bumper but has the grille. Engine was left out with the heads off and rusted up when a previous owner died during the restore. Still has the rear end and tranny but who knows if its sound or shot. I need a fender and the rear bumper and if the interior is good I may use some of it. Other than that the rest would just be spare parts. Im still thinking I should jump on it for that price. Anyone agree/disagree?

By the time you buy all the little parts you need, not to mention the larger ones you would spend as much if not more. Anything you don't use immediately is a bonus.