Double Double, toil and trouble
There is no possibility of using 2 Scepter's of Avarice in the same area.
From the FAQ:

Q. May I use the Bag o'Many Things to duplicate the power of a Relic in a region where that Relic already is? For example, may I use the Bag on the Scepter of Avarice to quadruple my region's income?
A. No. The power of a Relic cannot be duplicated in a region where that power already applies.