And so, what simple inexpensive host would anyone recommend where I could bring in my music track and then the vocal track that I can tweak with VST3, then import back into my Sonar 7 pro?
 

Sonar Artist will do the job. Platinum is the one I would recommend and you wouldn't have to import or export. Just use it as you do Sonar 7.   

Music Creator 7 is VST3 host too. Like SONAR it will require Win7 or newer (although it probably will run on Vista).

Being retired, I appreciate the advice of Sonar Artist. It's definitely a better buy for what I need it for than the $500 platinum. As mentioned earlier, I'm very comfortable with Sonar Pro 7. I know it intimately. I also see that there is a free trial where I can check out my problem plugin.
Here's a stupid question. If I load Sonar Artist, will it kick out my Sonar 7 or disrupt it any way? I'm assuming then that Sonar Artist has VST3?
 
Thanks so much, everyone for your help. The last time I was on a forum for help in recording a midi file to a wave was with Cakewalk 9! The forum was a god's send.

Parts of all Cakewalk DAWs are shared. Installing any newer Cakewalk DAW will update the shared utilities. The new shared utilities should work OK with SONAR 7.

rubicon 2008
Being retired, I appreciate the advice of Sonar Artist. It's definitely a better buy for what I need it for than the $500 platinum. As mentioned earlier, I'm very comfortable with Sonar Pro 7. I know it intimately. I also see that there is a free trial where I can check out my problem plugin.
Here's a stupid question. If I load Sonar Artist, will it kick out my Sonar 7 or disrupt it any way? I'm assuming then that Sonar Artist has VST3?
 
Thanks so much, everyone for your help. The last time I was on a forum for help in recording a midi file to a wave was with Cakewalk 9! The forum was a god's send.

I wish I could be of more help but I don't recall much about Sonar 7. It was a long time ago that I used it. Which ever version of Sonar you choose to upgrade to will not break your Sonar 7 install. You may need to upgrade your OS though. 

Anything before Sonar 2015 is orphanware. Check out music creator it may be a solution. I don't know the specs but they are posted here.