Like the title's gonna show I would need a copy of the open source ARToolKit v6 library to make custom edit for an Android implementation. Thanks in advance. Ps: I already downloaded the ARToolKitX version, however I need to make even more changes to make it in pair with the V6 library.
ARToolKit 6 was, unfortunately never released publicly. The sponsor DAQRI withdrew the efforts prior to releasing it open source.
The closes you can get is looking into ARToolKitX which is the successor of ARToolKit 6 and was released by the same team shortly after ARToolKit 6 got discontinued.
This link should have everything regarding ARToolKitX https://github.com/artoolkitx
I hope this helps a bit.
Also here is the official website of ARToolKitX: http://www.artoolkitx.org