Regardless of the amount, you paid for a service and that service has not been fulfilled/met. It might be just $5, but that's $5 someone has effectively stolen from you. What if they've done this to ten other people? Now it's $50. The amount doesn't matter, it's the principle. People shouldn't be allowed to get away with it, or they'll keep doing it.

I'd go ahead and start a dispute, see if they can magically re-appear and provide you with your art before you need to escalate it to a claim. If they do, fine. If they don't, they learned they can't steal from everyone.

And if you have proof they're ignoring you, post a beware.

Almost a month is excessive. What site? Can you tell if the artist has been online and avoiding your message? Is there an indicator that they read your message?

Sounds like you'd need to refresh a lot to see if you could catch them. Not really worth it. Sounds like the best course of action is the dispute. I'd send one more email and wait three days before filing. Depending on how they react, might put up a beware on their attitude if they contact you.

Remember not to close the dispute until you have the art or the refund. Once it's closed, it cannot be reopened for any reason.

Charge back. You can always repay them after they complete the artwork. Remember that once you start a dispute DO NOT CANCEL IT because if they dont complete the artwork, you cannot open it again.