Second, property law. Unless you have specific clause in your contract that the organization must ask for your refusal before selling to others, most courts would not enforce it by your words. Most courts frown at first refulsal right and option contract because they may be viewed as restrictions on alienation, therefore, invalid.
Third, constitutional law. When you say discrimination, you have to find a specific statute to support you. Without such information, I would say, no, for the reason that the organization is a private entity so that you can not hold it liable for violation of your constitutinoal right. There is no government action. Simple just like that. Even if the organization is a quasi-government, you would rather claim 14th Amendment due process violation because they did not notice you before selling to others. Discrimination does not always work because you cannot raise anything like gander, race, alienage, or anything like that in your claim so that you have the burden to prove the government action is not rational. Believe me, 100% of time you will lose.
Offer does not bind anybody, the contract does.