Gas everywhere but in the tank

I run to the store (okay just for fun).
On the way out I notice that the PO left the petcock in RES.

When I turn it - one small 'click' felt through the handle. Other than
that it turns freely - no further clicks.

Sure enough - later that night - the drip and stink begins.

I siphon most gas out and attempt to pour the rest into a funnel and tank.

Now I've got an empty tank (hooray paint!) and a leaky petcock.

While I have searched and read I still have some questions:

1) Should I buy the rebuild kit or take the o-rings to a store?
2) If I should buy - who is best online for a guy in the states?
3) Anyone know a gas-resistant sealer that I can employ in a pinch?

Thanks again folks!

 

I got my kit from partsnmore.com and never had a problem with it.
Some folks say they have bought other brands and they don't fit right.
They have a $35.00 min. order, shipping is free and fast.

 

I have used Home Depot o-rings for my rebuilds without trouble. I did use a new factory disk and tank gasket in my overhaul, but everything else was sourced elsewhere. Most Permatex sealers claim fuel resistance but that does not equate to fuel proof. I would suggest you go to Permatex's site and look up their applications chart, very handy to print and have around.