Please don't part it out! The five-speed is a very rare option, and the silver/blue combination is also sought after. Either save it, or pass it up.
The others are right, it will be costly to properly restore the car. However, restoring a 280 SL (for better or for worse), as opposed to the 230 and 250, is most likely to allow you to re-coupe costs down the line (higher resale value than the others). All sheetmetal is still available. A 280 SL with these options, in excellent restored condition, will easily fetch 30k, and likely much more, especially once the economy recovers.
If you're not daunted by a project (and you have the patience), bargain with the seller and see how low you can get it.
Save the car, document the process, and be a hero!