Remember that you are going to need two reamers
Finish reamer for the rifle chamber
Die reamer for a full length sizer that will have to be made, which HAS to be smaller than the finish reamer
JGS and Manson will do a great job for your, with a couple of month leade time. Hendrickson will take a year.
PTG went through a rough time a while back when Dave had back surgery. I think that things are much better there now.
This -
And you’ll have to have the sizing die hardened after you ream it.
I don’t know how long Dave’s custom reamer time is - I have a custom 308 reamer on order from PTG now, but have done a custom 280AI, and 260 reamer from JGS as well.