I would not at all be certain this gun shipped as a 3T. A large number of Model 14 revolvers from the "no dash" through the -3 shipped as 2T guns (Magna stocks). Having collected them for 40 years, I've seen a lot more with numbered Magna stocks than I have with factory original Targets. Sure, there are plenty of 3T guns out there.
If you do want period-correct Targets, they will be the diamond "football" style, and they won't be cheap. On the other hand, the gun would look perfectly original with diamond Magnas. Or, you could just leave it as is. Nothing wrong with it as a shooter in its current configuration. If the target stocks on it are too big for your hand, look for some diamond Magna stocks with the tapered shoulder.
The top gun in the following photo has Magna stocks that would be correct for your revolver.
Correct Target stocks would look like those on this Model 15-2:
These are GA, but walnut in the same configuration would also be correct.
Searching eBay would be a good choice if you decide to go looking.