Hi --
Sorry to hear that your ebay purchase didn't go so well (yet). I happen to sell (and buy too) many item on ebay. A vast majority of the transactions go smoothly without any problems. Unfortunately every so often there are those cases, where things often don't go so smoothly.
Now in your case, you noted that the person has perfect feedback, so hopefully this can get worked out. Give the person a few days to respond, some people don't check their ebay email every day or they may be away..this DOES happen. However, I'd be a little annoyed that the seller stated one thing in the auction (factory sealed AND earplugs included), however did not deliver the NEW and SEALED item complete with headphones. See what his response is first. If I was you I'd wait to hear his reply, and request either a full refund or lower price (I'd buy my own earplugs). Most honest sellers cherish their reputation, and are willing to work with you. However, if you are not satisfied with the response, then you may file a complaint with paypal or ebay.
Paypal protection is as follows (copied from ebay site):
PayPal Buyer Protection is offered to buyers in an effort to make our online trading community a safe and secure place. At PayPal, your security is our top priority. With PayPal Buyer Protection, buyers are eligible for up to $500.00 USD of coverage at no additional cost, for tangible items purchased on eBay and paid for through PayPal. To see if an item you're about to purchase is covered, look for the PayPal Buyer Protection icon in the Seller Information box on an eBay View Item page.
If you need to file a claim on an item you've purchased, please read through the requirements below. PayPal transactions can be covered by either PayPal Buyer Protection or the Buyer Complaint Process depending on certain requirements. PayPal will determine the appropriate coverage for your claim during the investigation process.
Buyers
PayPal helps you buy with confidence on eBay. When you use PayPal to pay for a qualified listing, PayPal Buyer Protection provides $500.00 USD of additional coverage at no additional cost.
Make sure a listing is covered before you make your purchase. To find out, look for the PayPal Buyer Protection icon in the Seller Information box on an eBay View Item page. If your purchase is not covered by PayPal Buyer Protection, it will be likely covered by PayPal's Buyer Complaint Process.
PayPal Buyer Protection coverage is: $500.00 USD. To see the equivalent coverage amount in your currency, click here.
Before filing a claim we encourage you to work directly with your seller as most issues can be resolved through direct communication.
PayPal Buyer Protection covers:
Items paid for with PayPal and paid to the seller's email address associate with the listing (to make sure you pay the correct email address, use the grey Pay Now button found when listing closes on eBay)
Items not received at all or received significantly different than what was described in the listing
Items purchased on eBay - when paying for your item, make sure you select eBay Items as your Payment Type
Tangible items (physical goods that are shipped to you) only. Services and intangible items are not covered
Limitations:
You may only file one claim per PayPal payment
Claims must be filed within 30 days of the PayPal payment
Does not cover cases where you are disappointed with the item you have received
You are limited to two PayPal Buyer Protection refunds per calendar year. If this limit is exceeded, there is no guarantee for full recovery. You will be awarded only what can be recovered from the seller. However, it is possible that the claim be resolved through the Buyer Complaint Process
You must be willing to provide information during the investigation process. If we cannot obtain the necessary information the case may be cancelled without a refund
