Need a shipping box for Technics SL-1200-MKII

Find a UPS Store near you. They will pack and ship it for you. If anything happens to it, it's all on them.

do what what abucktwoeighty says .

UPS store will charge arm and leg. DJ Odissey box you can get used $25.

I wouldn't trust UPS to pack a table. The tonearm needs removed (cartridge first). Then, the dust cover needs removed and packed separately. If the platter comes out, that should get pulled.
Now, UPS or any monkey can pack it all up safely. Keep in mind that packing and shipping the arm and cartridge takes a little care. A broken needle will ruin all. Once you get it there, you do know that setting it back up will take some skill.

Go to mrboxonline.com. They will custom make any size box at a reasonable price and send it to you. They also have packing materials.
I purchased made-to-order double boxes and styrofoam sheets from them to pack & ship a pair of Dunlavy IV-A speakers to England. Nice price and nice people. (Fortunately, for me, they are local and I could pick up the boxes.)

I highly recommend double boxing the unit. Try to find a box somewhere, like perhaps from behind Best Buy or similar. Then grab a couple other boxes so you can cut them and line the main box with a double layer. Maybe even triple layer. Use a box cutter or razor blade, cut the boxes so you can slip inside the main box on all 6 sides. We ship aerospace parts this way and it works great. Your new used box will be super strong.
Good luck, John

UPS is the best and they charge an arm and a leg because they are worth it and they will make good (only if they package it) if there is damage so thats the only way to ship anything you care about. They are good - bubble wrap everything so you can drop it off a 10 story bulding. People have issues with UPS because they take the cheap way out and use them for shippimng and NOT packaging. Their guarantee is only good if you USE THEM to package it for you (and then ship it).

UPS is the best, hands down.  (many hifi dealers and manufacturers will not use fed ex).  Dont say they are not good if you have not tried them and see them pack something.   They are pros at packing. It costs "an arm and a leg" because its the only way to trigger the insurance. if you let them do it, its $80 and if there is breakage, being they packed it, they pay you very easilly. If you spend the $25 and pack it yourself and send UPS and ther is beakage, you are on your own cause UPS has no way of knowing you packaged it properly.  You get what you pay for in life.  

The Technics is the same size as the Stanton ST 150.

If you have a Guitar Center, Best Buy, or DJ store in town, see if they will give or sell you the box. The Stanton is heavier than the Technics. I purchased my Stanton from Sweetwater, which is 2/3 of the way cross country from me and it arrived in perfect shape. You will need a separate box for the dustcover.