There's no way back from a port job on a double rifle.
At thousands to tens of thousands of dollars for a re-barrel job on a double rifle -- it's just not like screwing a new barrel on a bolt gun if you don't get it right.

If you want to re-regulate a double rifle for some load which is not the load it's set up for currently, have it re-regulated.
The cost isn't much, and doing so won't wreck the value of your double rifle. Porting a double rifle will definitely have a detrimental effect on it's resale value.

Cheers
Tinker