That's why I only send by tracked/signed for (or just one of, if both not offered) when posting internationally. I'll only post by Signed for/Special delivery (if over £50 value) within the UK too. Yes, it costs more but usually all is good and piece of mind for buyer and seller.
Funnily enough it seems that international tracked OR signed are more expensive than both but not all countries offer it.
Pity it will only cover up to £250 with enhanced insurance but that usually covers most items so.............
I think I've only had a couple of "disputes" and as all were sent that way, Ebay will refund the buyer and let the seller keep their money too.