I have, actually my Father has and gave me copies, of lots of Beauchemin information from Sorel. My father owns a House built by a Beauchemin in 1886-88 on an island bought by Paul Beauchemin (son of Augustin Beauchemin) somewhere around 1854. My parent's house was built by Paul's son Louis (my great grandfather).
For a while the island was known as "The island of the Beauchemins" in the Sorel area because only the sons were allowed to build houses on the island; thus all families on the island carried the Beauchemin name. The Beauchemin daughters had to leave the island and their husbands were not allowed to build their houses on the island.
From our research there seems to be 2 major unrelated groups of Beauchemins in the Sorel area. We've documented our branch which is the "Hus-Beauchemin" decendants.