Why not just get one of the readily available varieties in the list found here:
Post 452044 (https://www.thevespiary.org/talk/index.php?topic=13031.msg45204400#msg45204400)
(GC_MS: "TLC alkaloid determination of Morning Glory seeds", Tryptamine Chemistry)
Although, it would still be good to find the requested information and include it in the thread linked.