Unfortunately, the application is not available for purchasing from anywhere on the Internet since the official website is also discontinued. I've searched on other website as well, but couldn't find anything related to the availability of EasyAcreage.
I've seen that other developers created apps and services that can be used as an alternative to EasyAcreage.
For example, you can use the following online service to upload your KML and then calculate the area, exactly what EasyAcreage did: https://extension.unh.edu/kmlTools/
