I have had them reline a J D Dougall hammer gun "highest quality" with Lockfast setup and really, really nice damascus barrels, but totally shot out (pitted, thin and rivelled). As a matter of fact they also restocked it and built a new trigger guard from scratch.
The gun was originally a 13 bore as the proof marks indicate.
I think that it is now balanced just as it was on day one (around 1874 or so).
Funny enough, I bought the gun in Paris but it is inscribed on the rib to a gent in St Louis, Mo. So it went from the UK to US back to France and now back in the US... Not to mention a trip to UK for relining.
A traveling Dougall, that is.
Overall, I am sorry they (Teague) quit doing it.
Best regards,
WC-