OD is 2 inches
Length 11.5 inches
length beyond muzzle 4.25 inches
Not sure how heavy only scales I have access to is my powder scales (I live away during the week).
I have a T8 on my other rifle and the weight is similar if I hold one in each hand!
It does have a plastic bush. The mod is coming off of a standard Tikka T3; I beleive the Tikka and Sako Barrels are the same so if yours is a standard sporting profile chances are it will be a perfect fit. A replacement will only be required if your barrel is thiner than mine which I would doubt, it will be the same or larger if larger any rifle smith or engineering company should be able to quickly do this work for you. Failing that Border Barrels will be able to provide a replacement.