wix has on its "wish list" an IP block feature, but that would not even go as far as you need.
If you had your own web server, for example nginx, you can add the geo-location package and add country blocking in minutes.
My experience with dslreports, which as you know is US/Canadian/English/French only, is almost every single page access from far east countries is people attempting to cultivate an account that can then comment-spam. Very few bother to use a VPN to disguise their location.
