Holy crap! Is this the first time Toei's done this? With the Knife censorship I mean. I didn't know this kind of thing happened in One Piece.
As for the DVD thing, the Japanese DVDs don't come in Boxed sets, as said before it's a Singles-only release, and each single is EXPENSIVE!
If you can, I'd recommend getting the FUNi DVDs as they come out. they include the Japanese uncut version, and if you're after Raw DVDs, you can shut off the subtitles.
I don't say this to plug FUNi or anything, just… getting the FUNi DVDs is a LOT Cheaper than going after the, literally hundreds of OP Singles for 3500-4500 yen ($35-45 a Piece)
For the price of one 3 Episode Toei single, you can get one 13 episode FUNi Boxed set.
But if you have the money and insist on breaking the bank on the Toei singles, then Amazon.co.jp, CDJapan.com, and Play-asia.com all sell them.