Rust's "American Record Label Book" indicates that the LaBelle label was applied over existing Columbia stock during the years 1919 and 1920. These records were in the A.L. 5000 numerical series and were, at Columbia's insistence, invariably anonymous. Nevertheless, a diligent researcher might manage to winkle out the identity of the artist, given the current state of Columbia label scholarship.
Rust does not discuss any other numerical series but the illustration in his book is from the 1400 series and does have artist credits. I know of at least two other discs from that same series and three from a 300 series that also have artist credits. The one that serves as an illustration in Rust's book (1418 by the Indiana Syncopators) has a listing in Jazz Records (6th Ed.) and dates from 1923. At that time, LaBelle appears to have been drawing from the same pool of material as Olympic, Majestic and Triangle and using the same catalog number as Olympic and Majestic, although it is not clear that there is a corresponding LaBelle for every Olympic or Majestic issue. The 300 series seems to date from 1921. All the 300 series artists credits were, as far as I can tell, pseudonymous. The 300 series catalog numbers do not match the numbers used on corresponding Olympic issues.