Every post I have ever read on this subject over the last 6 years always seemed to end in "reman tranny being installed". The only difference has been in whether it was a $6800 dealer reman or a indy shop at lower prices. I believe one guy actually posted a blow by blow of him doing the rebuild himself.
When I bought 6 years ago this was one of the issues I was aware of and checked with my indy who priced out a rebuilt tranny from one of the big engine/tranny rebuild houses available to the trade and gave me an estimate of around $4000 installed with a 3 year/36K miles warranty. I'm sure there are many quality transmission specialists in your area who could diagnose/repair this for you and get you back on the road.
GL with whatever route you take.

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