C&R transfers will only work with firearms listed on the BATFE webstie for C&R.
They can be shipped thru the Postal service since they're all classed as antiques.
Any BP handgun can be shipped thru the Postal Service at any time, C&R or not.
I have my gunsmith here ship all of my handguns, since he can us the Post Office. He charges me actual shipping + $10 handling.
Good luck finding an easy or pleasant way to ship your guns.