I can't say about nutrition, but my main worry after that would be what if the snake accepts the chicks, then refuses any other food?
What if your source dries up? or, what if it becomes necessary to sell the snake, it's going to be nearly impossible to find someone to take it if it only eats chicks.
If buying online isn't feasable, and unless you buy 50+ at a time it might not be, look into local shows. Almost every reptile show has someone who sells frozen rodents, and they can be much cheaper than a pet shop.
If your next show isn't for quite a while, look for local rodent breeders who might be willing to fill in the gaps for you until a show.
Gale