I usually take my barrel wall gauge to double gun shoots (Vintage Cup, Southern SxS)to check bbls before any possible purchases. A friend was looking at a Boss SLE damascus until we measured 15 thou in one barrel. The price did not reflect the thin barrel and he passed.
Try going to a Vintager shoot. Someone almost always has a gauge. You should probably contact the nearest group first to ensure the gauge gets in the car.
If you are near Charlotte we can get together and measure them.

Joe