Where do you suggest I find a box so that I can ship the PSR3000 that I am selling? don't have original.

Beakybird

Check out your local bicylce shop. They are perfect for this.

check your local guitar center, they have tons of old ones usually hanging around

Great suggestion. Beaky, when I sold my PSR 3000 earlier this year I used an old Kruzweil K1200 box. Although it was a little big I purchased lots of bubble wrap and styrofoam to cushion the board. It arrived to the buyer with no problems.

Don't be afraid to cut a box down. When you take it apart, carefully inspect how the sides or top are put together. Use a box cutter or sharp knife to do the cutting. give yourself a couple inches for bubble and peanuts. Use good packing tape and you're good to go. When shipping large like a keyboard you can easily be charged extra for having an awkward sized package, so try to be as frugal as possible without sacrificing the safety of the keyboard. I usually wrap the keyboard twice in bubble wrap and fill in the spaces with peanuts, air bags or I've even seen real popcorn (???). Be sure to put a small piece of cardboard over your screen and even cover the keyboard itself to avoid them getting pushed down or broken.

You can also just drop it off at UPS, Fedex etc..and let them be totally responsible to get it there safely..

Packaging may cost a few more bucks, but it is on them for damages...no argument!!!