By that last sentence it sounds like you should just sell it as non-obfuscated source. It'll probably leak at some point if there's demand for it by pirates but

By that last sentence it sounds like you should just sell it as non-obfuscated source. It'll probably leak at some point if there's demand for it by pirates but nobody legitimate is going to use a stolen library without a license. A money back guarantee is probably a good idea, would it be cheaper to just do that as a payment from you to them than them doing a chargeback?