Adrian, 

You can place an order for individual irons through any authorized Titleist retailer.  If you give them the serial # off your current set, then they can go ahead and order the irons matching all the specs.  As far as teegolf.com goes, we don't have any online only retailers, so make sure they have a store front and show up on our golf shop locator (below).

http://www.titleist.com/find-a-golf-shop/

Cameron

1-888-TITLEIST 

I am a senior golfer and play Titleist T300’s. I would like to go to a lighter shaft around 60 gram is my current clubs are getting more difficult to swing and hard on back. Can you let me know the best place to inquire about new shafts. I can have them installed locally or where purchased from. Any recommendations where I can obtain shafts comparable with my clubs. Thank you.

Not sure of your budget but either a regular fitting or Titleist Thursday would be recommended so you can get the right shaft for your swing with T300’s. Once you have the right shaft picked you can find a shop that will change out your existing T300’s for the new shafts using the specs from your fitting. Good luck.

What shafts do you have now?The Tensei AV series red am2 senior graphite shaft would be light

Since you specified a 712 AP2, that club was released 9 years ago. You can widen your search for a 714/716 as well (all as used clubs). Even a 718. Short of upgrading to a full T-series replacement, I've been to 3Balls, Global Golf, Dallas Golf, and 2nd Swing in the past. At this point, most likely someone would be listing a 3 iron because they have since replaced it with a hybrid/driving iron. Single counterfeit 3 irons would be uncommon. Ironfinder.com has a 712 3 iron in inventory. They specialize in single irons. I'm LH so it was never valuable to me.