Need help replacing a part

I looking for a whole new Carburetor for my 25XD (Serial: A147629).

Problem 1.) can't find the serial on the website. I'm assuming its in the middle option
Options given to me to chose from in serial numbers:
6443973 THRU 0B238463
7209533 THRU 0A730006
9415101 THRU 9507380


Problem 2.) Assuming it's under the middle option of "7209533 THRU 0A730006", there are two options
CARBURETOR (MERC 25) (MARINER 25)
CARBURETOR (MERC 25)(MARINER 25)

Problem 3.) Under either option, the Manual Carburetor has two options. WMC-11 or WMC-26 (
I have no idea what WMC is or how to tell which one I have

Edit: Here is a link to where I am:
http://www.boats.net/parts/search/Merc2/Mercury/25XD/parts.html

try here http://www.seawaymarine.com/
6443973 THRU OB238463 should be your engine SN series.

Awesome help guys. I really appreciate it.

I'm having problems finding the part, now that I know what I need.

I need the WMC-11 Manual Carb.

It seems they've stopped making my model's parts

Edit: Would this work? http://www.crowleymarine.com/parts/308931.cfm

@Kim, The thing has been rebuilt so many times I think we just need a whole new one. The most recent problem was: We started the motor up... ran fine for about 30 seconds, then all of a sudden it Revs up as high as possible (really thought it might blow up). We tried to kill it via kill switch, but it wouldn't turn off... and it was going full blast. Only way we got it to shut off was by pulling the fuel line and letting it run outta gas.

Was the motor running on a hose when it took off? Never raise the throttle above an idle when running a motor on a hose with no exhaust back pressure.
2) does the motor restart and run normal at idle now?
3) have you checked the throttle cam adj for proper adjustemnt, if not properly adjusted it may go overcenter and stick in the WOT position.
I do not think a new carb would help. If you could find one.