I was thinking that it would be cool to have flowable silicone at YYE
Too true.
http://yoyoexpert.com/product/yoyojam/silicone/index.php
This can be used as o-rings, and they are flush!
thats still not flowable,lol 
You can pick some up at a local hardware store. Just ask for flowable silicone, gasket sealer or window silicone. its around 4 bucks here. later.
Keep it spinning