Hey Mitchell .... I'm totally striking out in finding any info on this company. What magazine did you read this article in?
A workable option would be to pick up an aluminum barrel fron a company like Jordi Rubio and then scratch build a counterweight for it. I'll keep looking though.
Not sure if the new Academy (if and when it comes out) M3 will have the weighted barrel or not. They say it will be released this fall.
Happy Modelling and God Bless
Robert