I see you've got some brand new feedback so I'll assume you managed to pay. Sometimes there are weird 'glitches' that cause little delays and disappearances and when you're trying to pay, these can be a bit unsettling.
When was the last time you deleted your computer's cache and cookies (temporary internet files)? That works like magic for a lot of people, - it seems sometimes there may be a clog in the pipes.
Otherwise I find the surest and easiest way to pay is from my Purchase History. Once you 'commit to buy' the item goes to your Purchase History, and to the right of the listing there is the phrase Pay Now. Even if the seller has "sent an invoice" for the combined rate or whatever, the change will be reflected in the total you pay at the checkout using the Pay Now. It's fast, easy, and paying from the ebay site is 100% safe.
Enjoy your new stuff. 🙂