Sonar on Macs....

So due to the drastic downturn in my music composing business (Reality TV overtaking Docs) I have been forced to do audio recording and mixing jobs on ProTools at a couple of recording studios.  Those studios have older Macs and PT systems and I sorely miss working in Sonar when I am there.  I can do tons of things in Sonar so much quicker,  like rendering multiple :30 or :60 commercials or a wav file for a 10 minute informational video with a quick bounce,  as opposed to real time.
 
So when I go work at these places, will I be able to put my version of Sonar on these older macs?  My question is both technical and legal.