Holderreads has great stock for sure, but are not the only source for quality fowl. Maybe take the time to search out the others who breed quality ducks and what their prices are. Also just because you order from the top does not make every duckling show worthy. Just wanted to point that out so you are aware that even the high priced ducklings will have culling that needs to happen for a breeding program.
Now a subject that hasn't been mentioned is selling of hatching eggs and live birds. Since you are still a minor is your mom going to become NPIP to include your ducks? You will need this to ship, and more for states like VA. Something else to think about. If she doesn't want to do that, then selling only locally would be your option. If ths is the case does your local market have a want for high quality ducks and the prices they get?
Just more to think about since there is a difference between pet quality duck prices, and show duck prices.