Just to give you an example....
Stomper was 3 pounds at 8 weeks. His parents were 5 and 7 pounds. The breeder said he would probably be 8 pounds. When I took them to the vets, they first said 10 pounds and then changed it to 12 pounds! Stomper is now 17.6 pounds at 1 1/2 years old! You never know what you will get. I would love him BIG or small!
I would guess that your little guy will end up being over 8 pounds. That is just a guess from his current weight.