With TC's for both the front and rear sight heights to be correct for a barrel depends on the barrel length and what cartridge the barrel is chambered for.
For Contenders, between the old and new styles of screw removable sights there are 6 heights for front and 6 for rear. The fronts sights on octagon barrels are permanent, so only the rear sight can be changed.
The heights are in inches... on front sights measured from the top of the barrel to the top of the sight blade; on rear sights from the top of the sight base to the top of the sight blade.
So if you are asking for help to determine correct sights you'll need to list the barrels length and the cartridge its chambered for.
Ladobe
I don't have complete sight charts, but do have some of them for 10, 14, 16 and 21" barrels.