I am almost in the same situation as you described. Got a clot in subclavian vein November 2013. After a few months, no pain or any issues with the arm apart from slight redness at the end of day.

I still can't decide whether to do the surgery or not. Would you do the other side as well?

I suppose I am afraid of developing pain after the surgery and as I have zero pain now it's a hard decision. Btw I am still on Xalerto and will be till I decide whether or not have a surgery. I also have a lot of collaterals developed but it seems they also get compressed when I raise my hand.

My surgeon said there is no harm in waiting and that it won't affect the outcome of the surgery if I wait. I am in UK, btw.