Acts mentions only TWO men named James, James son of Zebedee was killed, thus it was James son of Alphaeus who rose to lead the local Jerusalem church. This is who Paul is referring to in Gal 1:19. There is evidence for this, while there is no evidence some “third” James came along.
Exactly what I was hoping someone would bring up. The fact is there are only two apostles named James in Scripture, thus it was one of them, in fact it was James son of Aphaeus (and thus actually a cousin, not literal brother).
No, there is no evidence a “third” James exists. There were only two apostles ever named James, Acts mentions only two, one was killed, thus the son of Alphaeus was “James the righteous”.
I was hoping someone would bring this up as well.

It is worth noting that whenever Protestants cite the usual “brother” passages they ignore the “women at the foot of the cross” passages which provide important information. First of all, we see “James and Joses (Joseph, same word in greek)” who are PREVIOUSLY mentioned as “brothers” yet at the foot of the cross it says it is ANOTHER Mary who is their mother. It is worth noting that ONLY Matt and Mark mention “brothers”…YET BOTH ALSO mention “Mary mother of James and Joses” at the foot of the cross.