Need recommendations on club

I’m in the need of a new 6 iron. Currently I am rocking the Taylormade M2 iron set and I absolutely love them. I’ve had them for 6-7 years at this point and I plan to use them till I can’t anymore. A buddy of mine lost my 6 iron and I’m in need of a replacement. Would y’all recommend I just buy a M2 6 iron for the set or is there a better 6 iron specifically y’all would recommend. Also I totally could use some suggestions on websites to buy preowned clubs. Not looking to spend a few hundred on one club lol.