What you could do, if your GM temporarily promoted you to co-GM and gave you an empty page, is place all the tokens you bought onto that page and then revert back to a being a player. The GM would still be able to use those tokens as default for sheets or copy/paste them onto other pages as dressing etc... To be fair it might just be easier to gift them as Pat suggested unless you really want them tied to your account for your own future use :)