I believe many sellers don't want to know these measurements and few have the necessary equipment to obtain them. Even if they do, who is going to believe them in this day and time.
To his credit, this seller has revealed that one barrel has a questionable wall thickness. At this point, and if Mr. Boyce still wants the gun knowing what he now knows, he should probably either purchase the equipment to measure the barrels himself or have the gun shipped to a someplace like Skeets Gunshop for inspection and measurement. Skeets told me it wouldn't them but a few minutes to do such. Money well spent in my opinion.