Hi scorpiusrose .. 2 weeks to advise a buyer that" i'm out of stock" is unacceptable.
Respond and request an immediate refund. Not forthcoming , go to the resolution center in your PayPal account and open an item not received dispute. Escalate the dispute to a claim.
Once that step is taken there is no need for further communication with seller.
Do not accept a cancellation if seller files one with eBay.
Can leave appropriate feedback.
http://pages.ebay.ca/help/buy/paypal-buyer-protection.html