I dont have experience with K86, but Rootpac-R is also supposed to be a very good rootstock for this. @Jose-Albacete has posted about it before: (bottom end of this post)
A few more links:
I got elberta peaches on Rootpac-R from Sierra Gold Nursery, in Yuba City, CA last spring and they have grown well. I warn it helps being nearby in CA to get it from there, @Shibumi can on comment this.
I plan on mound layering one tree to propagate Rootpac-R in the future but I won’t have any to give for a while.