I've recommended calling Thole up in September. The Mets would have had to ad him to the team's 40-man roster in any case this off-season, so they might as well give him a chance to show what he can do in the season's final weeks. The 22-year old Thole has hit an eye-popping .332/.400/.429 in 97 games in AA. He's fifth in the Eastern League in OBP, third in batting average and his 28 doubles tie him for 12th on the circuit. It's an interesting question how his contact oriented approach will fare at the big league level. I think he'll be fine.
Defensively, he's thrown out 31.% (25/79) of would-be basestealers, or fourth out of sixth qualifiying catchers. Thole's nine passed balls are the fourth most in the EL, and he's caught the fourth-most games in the league. Reviews of his defense have been poor all season from impartial observers. He's improved his receiving abilities, but evaluators were still concerned about his arm.
Note also, what a month in the big leagues will mean for Thole. At a pro-rated portion of the MLB minimum, Thole will make almost as much per day ($2K) in the big leagues as he would in a month in AA.
Both Evans and Kunz are already on the Mets 40-man roster. After a transient season, and Evans has found his swing with a .283/.343/.554 August in Buffalo. It would behoove the Mets to find him everyday AB when he's called up.
There's just not much in Kunz's record in Buffalo, especially the 29 walks against 35 K in 55 IP to suggest that he would be a valuable piece of an MLB bullpen. Sam (and friends) at Amazin' Avenue write at more length about Kunz today, but I view their take as wildly optimistic.