Well.
I suppose another option, if you know how to do this non-shiny, is to catch a wild oddish or gloom?
DP: Routes 224, 229, and 230
Pt: Routes 224 and 230
HG/SS: Routes 5, 47, and 48 (night) (Gloom)
Oddish:
Pt: Routes 224 and 230 (night)
HG/SS: Routes 5, 6, 24, 25, Ilex Forest, Safari Zone (Night)
I don't know ANYTHING about Gen IV RNG so I don't know if that's easier or not XD