Lost Miwok Artifacts Event

So to create one ring, I only need to buy ONE of those un-sealing things from the CS?
Also, is it possible to have both rings/more than one ring?

I might just work towards getting both rings.

No, It works like this. You hunt monsters and sometimes they will drop these urn looking items which you take to the Toh dude with an unsealing scroll and you might have a chance of getting one of the items you need for the ring. Which means you could spend up to 100k NX and not get what you need for the ring.

You can have both, and more than each one.