2008 LTZ V6 transmission swap

I bought a 2008 Chevrolet Malibu LTZ 3.6L V6 6spd (automatic transmission) as my first car a year and a half ago. I'm in love with this car. The problem is that due to the 3-5-R Wave plate failure, my car's transmission has crapped the bed. I have been looking to see if there are any other transmissions of a later year malibu that I can swap into this car. I thought about buying a tranny from a junk car from my local u-pull it but, the problem is is that there is no guarantee that that transmission won't have the same exact defect. The same goes with a refurbed transmission. My only option at this point seems to be if I can find a tranny that will swap into the car with the 3-5-R wave plate problem fixed or buy a
re-manufactured transmission at the cost of nearly 2,500 dollars. I'm really trying to steer clear of spending that much money on just the transmission let alone for a car that just turned 12 years old. Do i have any options?

Side note: this isn't a huge priority as I also have a jeep that I use as my daily driver. I have time to find a transmission as well as put it in, as a father son project.