Lower cost transmission options?

Well I wanted to use 2.94, 3.07 (Jeep), or 3.23 gears depending on what I can find for the best price. I'm building the car more for road-racing and high-speed handling than drag racing. I also want to be able to cruise on the highway to faraway places and get good gas mileage and have my engine last a long time. I figured with those higher rear gears the low-gear set for the transmission would help to make up lost acceleration especially off the line.

Looking at the link you posted I would need to get PN 12555A? It says it's for 1971-89, would it still work in my 1970 tranny? And then the forward drum would be PN 12554C? I'm looking at getting the rebuild kit, valve body, and converter from Cope Racing Transmission, is this the kit I should go with?

https://www.coperacingtrans.com/product_info.php?cPath=56&products_id=427