Tranny Swap

I'm considering working on a new transmission to go along with an engine swap. I assume my selections will be very limited, just wondering which tranny would work best.

Requirements:
1 - Able to accept TSX 6th (or similar gear for gas mileage)
2 - Fit in an EP3 chassis w/k24 block
3 - Includes/could accept an LSD
4 - Be economically reasonable (primary reason for swap = better gas mileage)

I would put a 6th on the EP 5-speed but I've never worked on a trans before and this car is my DD. I'd like to have plenty of time to work on the project and still be able to drive the car. When everything (engine and trans) is complete I could drop them in with minimal down time.

Also, if anyone could help me out with an approx cost that'd be a big help too. Thanks.

Your two best options are the RSX-S tranny, or get a 2nd EP tranny (most likely at lower cost) and work on that.

Take a rsx 6spd and put in the tsx sixth...Done!