JD JX75 mower but has a Walbro LMJ-16 carb?

The Walbro LMJ-16-1 carburetor can be gotten through any vendor that has the K10-LMJ kit. As the other parts that not in the kit they can be obtain any Kawasaki small engine dealer. Just be aware JD shows that the JX-75 came with 4 different engines so you need the model and spec of the to look up parts.
 
Also note there might be a few proprietary parts that must gotten through JD.

The Walbro LMJ-16-1 is obsolete per Walbro. JD does appear have an alternate but would to know which engine you have. The FC150V or the FJ180V?

Well that tells you have a 2006 model. The following should narrow down the engine.
 
Here is image of the shroud that was used on the FC150V

 
And this what the FJ180V looks like.

JD parts Adviser indicates the current replacement carburetor is PN AUC11726. Appears to list around $140. Google the part number for possible online sources.
 

Depend how stuck in place the main jet is. Item 11. To remove the main jet it requires a hollow ground straight side flat blade screwdriver tip. This helps to prevent climb out and damage to the jet. Once the jet is removed then you should be able to press out the nozzle. Not 100% sure as I can't find an image of the nozzle and some are threaded but you will know if once the main jet is out as if threaded it will a slot in it too.

Understand the problem as a small independent shop I see a lot of this problem of "Is it worth fixing vs replacement on equipment?". Water damage to aluminum is one that kills some equipment. I work on an old Tecumseh engine on a go cart last fall where the replacement cost me $75.00. The engine fired off on fuel induction so it appeared that the water damage to was about it. So I repair the flats, braking problem, and ordered a new carburetor.
 
Well when I got the new carburetor installed and started the engine up it ran fine for all of 3 minutes until it got warmed up. At this it started smoking like a freight train. Well I found oil in the intake indicating a bad valve stem seal so order and replaced it. Then the smoking all the time went away and only smoked heavily on acceleration.
 
The strange thing occurred on the leak down test. I had less 20% on a standard test but since it was OHV engine I disabled the valve train and did the test at BDC instead of TDC. Boy it went to over 60% leakage. I ended up pulling  the head and that when I found the cylinder completely worn out, it was even beyond rebuilding.
 
I ended up having to replace the engine with a less desirable engine from Harbor Freight per the customer request. But if it was up me I would just junk the go cart and replaced it with another one.
 
Costs to repair does kill a lot of engines and other equipment. Handhelds are among the worst about costs to vs replacement. I seldom I see walk behind mowers any more because even owners have realized it is a waste of time on the low cost units. Now JD mowers are not low cost units but there are still times must we called it and kill the equipment. If you are doing this for yourself then the labor costs are involved like when we do repairs for others so it would be your call.
 
Don't get dis in-hearten though as it provides a good learning experience and makes you a better tech. Yes sometimes need spend money to learn on things that are not repairable. But the good thing is we learn from so like going to school without the additional expense of the classes.
 

You said you had a Walbro LMJ-16 and I gave the Walbro kit number in post #3.

Mcgyver
Thanks, was trying to find a kit for the AUC11726 

If that is the case then the chances are slim to none as OEM like JD is no longer providing repairs parts below sub assemblies.
 
If you are old enough to remember we were once able to rebuild things like brake master and wheel cylinders for automobiles but now can only get whole assemblies.
 
We all are being forced into to being part replacers and not mechanics.