You should send an email and ask- though I would not ask just that. And if you want to breed later, I would not ask for 'breeding rights' so much as ask if there would be an opportunity to change to full if you title the dog and get clearances.
Cause, really, "breeding rights" are not (from good breeders) bought but instead earned.
Personally, I see that term as a red flag. And when you look at it from the perspective of the tens of thousands of dollars invested in each dog in a breeder's program, why would that breeder want to sell a puppy for $500 more (or any amount more for that matter) and let someone else build on their hard work?