Here is the link to the latest Turbo.264 HD 1.2.3 software:

Turbo.264 HD 1.2.3

You will need a Turbo.264 HD activation key to use this software.

Turbo.264 HD keys are no longer available for purchase, since the software is End of Life (EOL) and no longer developed.

Thus, this link is only for pre-existing owners who already have a key.