this is a good example of the St. Lunatics combining urban and country lifestyles with the imagery of an urban cowboy putting a saddle on a horse and wearing Nike Air Force tennis shoes with spurs rather than cowboy boots when riding a horse
the St. Lunatics consider themselves from "the country" (St. Louis, Missouri). This is still a major city to most, but compared to larger coastal cities, it's more out in the open. V-12 horses refers to cars they ride with powerful 12-cylinder engines.
he doesn't really wish he would find a seed in his weed. it's not good to have sticks, stems, or seeds in your weed (useless parts of the marijuana plant)... he is bragging, saying that it would be impossible to find that in his really good weed