Many CTA discs and others are available in Europe through the Austrian DJ Bernhard Gehberger. He recently went to Japan and met with the guys behind CTA, AMP and Audio Park. From his report from that trip, it seems like he is working on facilitating reissues of these out-of-print discs. Which would be of great benefit to the tango community if he pulls it through. Today they are both hard to get and expensive.
Good luck, Bernhard!