It would help to see the other side of the circuit board (and with it out you could check the date codes on the pots), but almost certainly yes V3. Also, you could see what transistors have been used, some are rarer than others.
This is the definitive Muff history pages The Big Muff History of All Versions Part 1
This is the definitive Muff history pages The Big Muff History of All Versions Part 1