Wheel Off Sets

[Isuzumu]

I have looked at a site which informs you about how to calculate the difference in off sets. Ok then, do wheel makers have the off set stamped on the wheel?
It looks like most of the new dual cabs have an off set around 30+, not sure of course, does not look goood for my 16x8 with 0 off set going on a new D.Max, plus they have 265/75 x 16 MT ATZs so they would be illegal anyway.
Thinking a set of Sunraysia 16 x 8 with 265/70x16 Cooper AT3s. They are just legal at 778mm dia, the MTs are 803mm dia.
The D.Max we want to buy has 255/65 x 17 Bridgestone HTs do not think I would get to much for them so the reason to buy a new set of rims as well, so help me out please 

[Black Diamond]

99% of wheels do have the offset stamped on them

[Isuzumu]

99% of wheels do have the offset stamped on them

Thanks BD