I may just go ahead and go RH.
Don't do it. Not for a big bore.
The cast on a RH stock will be all wrong for a lefty, and may play hob with how it handles recoil. In addition, part of the reason (real or imagined) for owning a big bore is a quick second shot. Tough for this lefty to do with a RH bolt. Take an action you already have a spin a barrel on it. .416 Rigby could be tricky, but a .416 Ruger should not be.
