Use Archive.org to dump games you physically own. If you own the arcade disc or a dedicated cabinet, downloading a backup is defensible. If you have never paid for the game in any form, you are technically pirating.
While the TeknoParrot software is easily accessible via its official website, the software layer is useless without the actual arcade game data—often referred to as "dumps." This is where becomes indispensable. The Problem with Arcade Data Longevity teknoparrot archive.org