The rifle looks very much like a New York gun with its single trigger and late, wide guard. I looked in "The New York State Firearms Trade" book by Swinney, Vol. 4, pp. 1672-1673, and an "L. B. White" was listed. He is apparently the same man who may have worked later in Indiana. White was working in Leicester, Livingston Co., NY in 1827 (newspaper advertising) and Moscow (suburb of Leicester) in 1833. Swinney went on to say most of White's guns, including under-hammers, appeared to be New York work, most had locks with New York dealer markings, and most showed up at New York gun shows.
Swinney mentions the reference in Seller's "American Gunsmiths" of White being in an 1860 directory in Indiana, and suggests it may be the same man...although he seemed to have some reservation, since most guns he had seen were New York in style...and he felt if the same man, the Indiana years were late in his life. Hope this helps. Shelby Gallien