Hovik,
They should contact the partner in Ukraine, who sold them the application. The partner will provide installation files. The documents should be in your Ukraine office. The other option is if they have signed up the support site, they can download installation packages there.
Any way, if you are going to migrate to another server and not familiar with 1C:Enterprise platform and applications, you better contact the experienced partner. That is recommended because there might be custom changes in the application sources, for example, and you need to consider this during updates.