An alternative option is to send it internationally yourself.
That way you will need at least their country, ideally the full address and can cost out for sending it yourself, then if they are happy amend global to a priced international rate
I did this not long ago for the US, we went into a lot of comms working out options.
The sale would have been excessive on the global option (but fully safe for me) and still pricey for full international tracking etc
Due to their feedback level, good comms and it not being a lot of money to worry about if it went wrong I agreed to send with “Royal Mail international standard” rather than fully tracked and signed for etc on the basis that there may be no tracking (and that in some countries any tracking may vanish) and I would not guarantee delivery (despite that they could stress for non delivery and raise an eBay case)
Instructions from them was to clearly mark their apartment number. I print labels directly from eBay or via the postage provider, and it was clear in the address but I believed them (receiving deliveries is very dependant on who makes the final delivery) so added the apartment number in marker pen as well
As it turned out the tracking came through fully at each stage, what would have been 75p UK postage and I charged £3.50 (the final cost when weighed was £3.20 so I ‘made’ 30p on postage) ….. I was unsure where I would hit the weight threshold as this could have happily be sent as letter size with card reinforcement, but as it was for the US I sent as a boxed letter with more packaging
The agreed sale was £6 plus £3.50 postage
They were charged an extra 63p in taxes
From my £9.50 I paid 78p in fees, and the £3.20 to Royal Mail
(Again I am currently on reduced fees, 80% off for that sale, plus an international fee and VAT on the fees)
As you could get stung by overseas charges it could be worth agreeing on a direct postage rather than dropping your sale price to compensate on their additional costs through eBay
It could of course not be worth your while, especially if you could sell in the UK
Usually when international buyers ask for a decision due to the cost I tell them that I cannot see the eBay global charge, and I’ll leave it at that (perhaps accepting a lower offer but only if it suits me ….. I think I have done no more than 3 direct international postage arrangements since beginning to use eBay global