Hmm...why not convert it to a 5 speed? That would be cool, one automatic and one manual svx in the garage
I can't imagine they would give you anything for a 15 year old car with a bad tranny if you traded it in. And selling it without telling someone wouldn't be cool, find a used tranny or 5 speed, you've got the resources, it's just a matter of making time. You do have 2 newer cars, if it was me I would narrow out my options before bringing it to its death.