Well besides me for the cost of shipping... just kidding of course.
Unsure of where you are located, but contacting a custom saddle maker may provide contacts. There are also collectors around the country who will do an appraisal, and may provide a buyer.
In my area, King's Saddlery and the pawn shops can both do appraisals.
Further, there are internet forums where you could get an idea from some of the members on both it's value and how to market it.
Depending on who made the bit, you may want to sell it separately, or you may find a buyer who wants both.
It's beautiful, from what I see. Good luck with the selling.