welcome to the dead atx club....sounds pretty close to what happended to me when mine when...i lost second the fourth gear synchros and had to limp my car down a short freeway run doing 70 in 3rd gear at something like nearly 5000 rpms i think it was
anyway, yup price varies somewhat but mine cost 2700 at the dealer which may have been a shop rate or warranty rate since i have coverage...i've seen some say 1500 but as far as i knw the atx itself costs at least that much...just seems to be an expensive part and labor
maybe u all can check around for lower replacement price than what u are being quoted because u can pretty much count on the dealership not going down on the price...and i dont think they are too interested in taking the time to repair your old tranny...they wanna replace so the can get your left nut along with the arm and leg