E328 is given as a second flag and assigned to the 1848 sailing; E358 is undated. The painted 1840–1850 source also shows E328.
Empire operated from Nantucket in 1843–1852, when sold to New Bedford. Nathanial Starbuck was the first owner and G. & M. Starbuck the agents both initially and in 1848.
Keep the explicit scope label independent; no alias or company identity is inferred.