j, are you looking for just the mufflers? or are you needing the whole exhaust system? if its just the mufflers, unless you are just looking for inexpensive.. you might offer to pay for aftermarket mufflers. somebody would give up their stock units if you bought them new boom cans.
Good idea, Poncho. If say, someone had torque loops I'd be more than willing to trade off my stock cans. They maybe have 80 miles on them. Bought Torqmasters The week I bought my Valk. Torque loops are like $300...
The oem exhaust keeps the dreaded "Drone" down .....changing out the factory cans WILL cause a drone unless you spring for the torque loops. The factory cans are not terribly restrictive anyway ......you NEED back pressure to an extent ......Here is an interesting thread over on the other Valk board fra a couple years ago in case y'all missed it : LINK
while torq loops are beneficial because they get rid the cats and add pipe length and back pressure due to the 360 degree loop, they are not essential. you could just run a straight pipe from the header collectors to the new equal displacement boom cans. with out a cross over, you have just 3 cylinders sharing one muffler. with a proper crossover you have 6 cylinders sharing 2 mufflers (volume).
that droning is a function of that inverted crossover pipe and the flow of exhaust gases from one side to the other is anything but laminar. the purpose of a cross over is to optimize scavaging of the cylinders.
so just swapping out mufflers is not enough. you need to eliminate that inverted cross over.
at first I thought to build a cross over system similar to drawing one.. after contemplative thought, why bother and just build 3 in 1 headers into a collector and squirt the whole thing out one side or the other into 1 bigass can.