Hi Bobby and welcome to the group.
I have looked into the Sirius dome only and placing it onto my own construction to keep the costs down somewhat. But that phase is probably a while away yet. I don't think you will have any problems in fiting the 12" into it.
A nice choice of scope that your wife has purchased, you will get many years of fun from it that's for sure. I may be a bit biased though.
Cheers
