I think the "Delacour" was a line, just as "D.B.L." was--at least this is the suggestion in a pre-fire catalog. Sandblasts were on offer, though nothing named "Knotty"---notwithstanding the fact that the catalog may not have been comprehensive. There are, however, images of sandblasted "Delacour" pipes in the pre-fire catalog.
The question, I think, is whether "Delacour" pipes were produced by Delco Briars, or whether we might say with some certainty that the "Delacour" were pre-1935.
The original eBay listing shows a "Knotty" but I can't quite see a "Pine" underneath it. There may be some sandblast over the stamp. Does it in fact say "Pine" and not "Pipe?" I can only see the words "Knotty" on the eBay listing and none other than "Delacour" in the post above.
I'll try to unpack my issues of Tobacco and have a look at what Delco Briars may have listed as having been on offer.