I would check the condition of each of the barrels (bore surface, chokes, barrel wall diameter, chamber length) and if in good shape I would definitely list for sale. But probably not Canada. I'd list them is the US and/or Britain. New barrels from Boss are handily in the 5 figure range. There may be a Boss owner who would like a multi barrel set that doesn't want to drop $35,000 on two sets of new Boss barrels.
A friend and I have both bought Manufrance Ideal barrels to create multi barrel sets. Very specific measurements must be taken at the breech to ensure it can be made to fit. Any sign of the forend iron?
There will be a serial number stamped on the flats. First thing I would do is get in touch with Boss & Co. and see if they have any information on where the two actions might be. The barrels were hand fitted to the actions, and not interchangeable ( hence the numbers), so it's unlikely they would fit on any other gun, Boss or not.
Two guns. Matched pair.
And, given they are marked 1 & 2 and are together, it's likely they were originally fitted to the same action, not two different actions. So from that standpoint they most likely were "interchangeable" on the original action. Although they probably had different forends.



























