Wow, why do so many people on this forum interject sardonic commentary because someone wants to do something that they don't personally find worthwhile or important? 90% of people would tell you that spending the ridiculous amount of money on a MBP isn't worth it.
Be sure to get one with either no serial number or a replaced factory one just for warranty purposes as it could hurt you and would certainly confuse anyone who you may give or sell the MBP to down the road.
You may also be able to repair the current scratches...if you are going to get a new one anyway, you might as well try this as worst case you make it worse and replace it anyway. I have one huge scratch on the bottom of mine and while I haven't had time to try this yet, I've heard good things about using these mechanisms on the MBP's paint type. I've used this on cars myself, but I can't say first hand how well they will work on the MBP. You have these options:
1) Use an abrasive to 'stretch' the paint (Scratch X and GS27 are two 'consumer' grade products...pro products are much more potent and have the ability of: doing a better job, destroying the paint if you screw up, and burning the hell out of your skin)
2) Use a touch-up paint to 'fill in' the scratch (you need to make your own touch-up paint which may require blending. Test this on somewhere other than your MBP and LET IT DRY as color changes with drying, especially in metallic paint blends. Certain powder-coating materials may also bring satisfactory results)
3) A COMBO. I would use a touch up paint and toothpicks to literally fill in the elevation change of the deep scratches. Let that dry for full set time and then evaluate it. If it looks good, call it a day. Since no touch-up paint is from Apple, exact color match is unlikely and so you now use the abrasive to literally 'blend' the touch-up and factory paint. Do this slowly and carefully because often when it will look the best is right before you completely destroy all you've worked on. Other chemicals, including polishes and waxes can be used to manipulate the color/pitch/hue/blend but once again, go slowly and give each 'round' time to dry and reach its final 'end-point'. Once you hit the good point in which you are satisfied, I would put some barrier over it to protect it as any type of touch up is not as durable as the original finish. A few members have ranted about clear covers which seem to be a great and inexpensive form of protection. Even if you don't want to use it all around, I'd consider it for the bottom. DO NOT put anything over the cover-up until you are certain that it has dried.
If you aren't up for manipulating the paint on your own, take the cover to people who are good at it, such as an automotive detailer who does paint manipulation. If they can do it, it will literally take them a few minutes to a few seconds. Then throw up a few bucks and go on your way to get your product to protect it.