Could someone transplant the Rinnegan from one of Pain's paths? Could someone transplant the Rinnegan from one of Pain's paths? 

For example, from the male Chikoshodo (summoning) Pain that the Leaf had in their possession.
I have to say NO. 

My reasoning is based on the time when Tobi is hunting for the Rinnegan after the death of Nagato. After he kills Konan, he finds the corpses of Yahiko (who was also the Tendo's body) and Nagato, and pulls only the body of Nagato to his dimension and leaves the body of Yahiko in the same place. If he would have been able to use Yahiko's eyes, I reckon Tobi would've picked that body as well. Seeing how he chooses to ignore Yahiko's body would suggest that only Nagato's eye truly matters and it's the real Rinnegan.