Maybe this link can be displayed only to logged (as patreon) so its only visible to patreons supporters and not any potential buyer.
Viewing post in Patreon Finer Integraion
This could work, but also it might hurt people discovering that you have Patreon support.
Something else I want to do is have a button elsewhere on itch.io that says "Use Patreon? Link your account" then it redirects you to a page where it shows all itch.io project pages that are eligible to be claimed with the Patreon account you just linked.