Gunsmithing Need Custom Die Made...Can Anyone Help Me

Whidden is a good bet.

Get one on order and in the meantime, use a standard seater for a 243. Not *ideal* but will work ok. In fact, if you use it carefully, it'll do a fine job.
 
+1 for CH4D. I have a set for a .408 cheytac and they are nice but you did say you are in need of a set rather quickly and getting a custom set made quickly is not going to happen unless they have a set of what you need already there. I think CH4D is a 3-6 month wait so the original set you ordered from redding may be the soonest you will be able to get them
 
You must be at least 18 years of age to use this site
You confirm that you are at least 18 years of age by continuing to use the site.