If I remember correctly you have the Hustler Z.
There is no "wing" on a Hustler Z.
The kit does have a MSRP of $149.00, it includes the carb jets, gaskets, hoses, filter and housings and such, all the hardware and the mounting bracket that the whole filter assembly bolts to.
This MSRP is for the parts only, I do not know what your dealer will charge to install it.
Here is a picture of what your mower will look like once the kit is installed, it is identical to the units coming off the production line today.
OK. I went to the site and checked it out. What I'm calling the wing is different then what's on the Super Z and is called a wing. In any event that doesn't sound too bad a price for carb kit, "wing", and filter set.