Hi AtreiusModels
The T12 is I believe a 12v brushed high tork motor favoured by Tug modellers for its high pulling power. We really need to know what model you are going to install the motor in to and the size and pitch of the prop. There are many similar motors available and providing the details of the model will help making the best choice for your intended use.
dave976

Agree with RodC, also need to know the voltage

I suggest that you post the specs of the motor that you are looking to find an alternative for, for instance is it brushed or brushless? If brushed what is the case diameter and length? If brushless is it an inrunner or an OutRunner? And what is the KV?