It is the younger Tarkin, no doubt about that.



Christopher Lee and Peter Cushing were the most symbiotic of co-actors for all their careers.



They are parallels, you see, in the Star Wars trilogy. Dooku reflects on Tarkin in the prequel trilogy, and Tarkin reflects on Dooku in the original trilogy.



So, you see - it is an allusion to the nature of their collaborations which reached a fateful conclusion in their casting for Star Wars.



But, in real life, Lee and Cushing were best friends in irony to this image.