Definitely the barrels are French. The lettering after Leconois is a word:
L'aîné, meaning "the oldest son". It is known that Laborde (1745-1760) was often named as
Le Jeune (the Young), which suggests a Laborde father (Bordeaux 1730 ?). However in the case of your barrels i would not discard the possibility that the epithet goes for the "oldest son" of such Leconois, the name of a less kown (so far) barrel smith; you know, Laborde being a whole pistol maker but using contracted barrel smiths for shotguns ?. Besides, one finds it hard to see Laborde forgering his guns with Spanish marks ... or has a Laborde lock been implanted in the dicussed shotgun ?
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Just for the fun, look at this hunting pistol by Laborde a Paris.
(Courtesy Galeriedemars)
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