I bought my Tikka WH in 7mm-08 off of gunbroker.com. You are right, they are no longer made, and thus very difficult to find - especially NIB.
With regards to your question of which is brighter in the 4200 series (or any other scope of equal quality) the 1" or 30mm, the answer is that they are both the same. I would believe that the 30mm tube would be brighter, but I have been told that I am incorrect. It is undisputable that bigger tubes allow for more internal adjustments (all else being equal) but not brighter.
I look at it this way. Take a tube that is pencil thin. Then take, say, the inside role of a paper towel role. Doesn't it seem that the paper towel role, because it is bigger, is thus brighter? Again, I think so, but everyone tells me that I am wrong.
Zachary