I've been searching high & low to find a company that will white label individually packaged seeds--like what you would find at a normal gardening store. These packages usually range in price from $1 to $4 depending on the seeds.
I have been involved in agriculture for over 30 years. The answer, like so many things is: it depends. Most states, but not all, regulate seed wholesalers and require a license. The licensing requirements vary from state to state-some are rigorous, others are like a library card. As to finding a white label company-you might be able to get one of the large established retail seed wholesalers to package your product for you. Or you might be able to find a company that packages food and they could convert part of their line to accommodate your requirements. If you would like to follow up, let me know.