360 year differences

I have a '65 Barracuda with a 273 and 3-spd manual. I am wanting to go 360/727 and bracket race with the car. The goal is to run 13.00. I found a guy local to me with two complete 360 engines. One is a 1971, the other is a 1974. He wants $75 for the '74, and $100 for the '71. My question: what is the difference between these two engines? Which one should I choose for my barracuda? Thanks!