KLX 125 Float stuck, switch broken.

Alright guys, a buddy of mine has a 2003 KLX125 that he rides with me on occasion but I keep it at my house and maintain it a lot of the time. Anyways, it constantly streams gasoline out of the carb overflow.(float stuck i imagine?) On top of this, the fuel switch has quit working the majority of the time so if you let it sit with fuel in it you come back to a puddle if you turn the fuel off or not. Im tired of it draining in my garage so I suppose I will try to fix it. (Outdoor dirt floor garage, not as bad as it sounds). I have the manual for a 2003 Yamaha ttr-125 which seems to be the EXACT same bike but it has nothing about carb leak troubleshooting so it would be nice if anybody had some info for me. I have never had a dirt bike carb apart so I have no very little clue what im doing. I also want to fix that switch. This little thumper burns, no no *uses* about 4 times the fuel of my 250 2 stroke and it is ridiculous.

$53 for a petcock? I think not! I will put a damn inline shutoff after the thing for $3 way before that. Is the 'seat valve' the same thing as the needle valve?

Well I fixed the fuel switch by flipping the gasket over. The one side of it was chewed up from crap that was inside of it. The brass tube that goes into the tank was full of junky crap that i would guess caused the float valve to stick in the first place. Anybody know a place where I can buy just the gaskets I need to take the carb apart, I would prefer to not have to buy a whole rebuild kit.