The Nigerian Scammers with feedback who have contacted you will have hijacked another member's account.

Others will be newly registered Scam IDs.

It's best to list Scammer prone items just  in an auction format as Scammers love Buy It Nows.

Although you can list as a BIN with  immediate payment required, that doesn't prevent  Scammers from paying with  stolen credit cards.

Phone eBay through Customer Support ( top of page) and they may refund your final value fees without the need for you to open  Unpaid Item Cases.

 http://ocsnext.ebay.com.au/ocs/cusr?query=1491&optionId=1506485434

Beware of  further spoof/phishing emails you may receive .

Don't open them and don't click on any links.

Run all your spyware, keylogging and virus protection and change your passwords regularly.

Be sure to have these buyer blocks in place. Go to:

My eBay > Account > Site Preferences > Postage preferences > Show >
Exclude postage locations from your listings from your listings > Edit .......and Select the countries you don’t post to.

Tick … Apply to all current live listings
Click …Apply

And

My eBay > Account > Site Preferences > Buyer Requirements > Show >
Edit .......and tick:

1. Buyers in locations to which I don't post
2. Block buyers who haven't gone through phone verification…
3. Only apply this block to buyers who have a feedback score of 5 or lower(Having a Paypal Account and / or Credit Card details on file overrides this block)

Tick all other blocks of your choice.

Tick …Apply above settings to active and future listings.
Click …Submit