Yeah, I'm pretty sure it was official, but it never got released outside of Japan (surprise surprise). Play-asia has had them on their website, but they're always out of stock and there's also a lot of incompatibility with games because of the missing analog sticks and shoulder buttons. But the saturn pad is great for fighting games, not for FPS's =P
Actually here's the link to Play-asia http://www.play-asia.com/paOS-13-71-m-7 ... 0-ohs.html
Yeah, it's a shame they don't have a price, but personally I would never pay 175 bucks for a saturn controller for a ps2. Especially when there are things like this http://www.bestsku.com/productsDetail.asp?PID=1143
I'd much rather just get a real saturn pad and then buy one of those then spend 175 dollars for an "official" one.