We'd be happy to send out any of our published cDNA constructs to interested researchers in the public domain – just get in touch.  But to make this process even easier, we've started depositing our plasmids with Addgene who archive, document and distribute constructs on a not-for-profit basis.  If you go here you should see all the plasmids available from us, with YFP-NavII-III leading the way.