I just thought of another potentially useful code. This one's from the Shark/AR past, more or less:
Buy [item] from PokéMart
As far as I know, there isn't a 4th gen version of this code that was quite helpful in generations past. This could prove helpful for times where you just need that one item (and only a small quantity, more than likely) and don't want to have to edit your entire pack for it. (Common example being Masterball, despite the 100% Catch code. Also the mega-rare berries like Liechi, Lansat, Micle, and Jaboca and some one-time/hard-to-get TMs come to mind)