Just wondering if Sonar ships with something similar to voxengo Curve EQ?

No,  but Voxengo CureEQ is right for the job. 
 
http://www.voxengo.com/product/curveeq/
 
Not the best Video but it visual,  https://www.youtube.com/watch?v=wHmXyYx3-sk
 
 

There are pros and cons to curve-matching software. I've tried it in the past with occasional success, but there are various considerations. You might find this article, Curves of Steal: Fabulous Frequency Felons helpful in sorting out the different options (it also covers the Voxengo software).

Very nice article Craig Anderton,
 
It was enjoyable to read and very informing about the comparison of the three mentioned software Frequency copying products.   I first purchased Cure EQ back in 2006 and wasn't that pleased with it, however, it has gotten a lot better over the years I must say and I may update my 8 products while Voxengo is having an upgrade sale.
 

Jul 1, 2016: Dear Voxengo users,

During the summer months of July and August, 2016 we are offering 20% discount on all Voxengo purchases, including upgrades.  Moreover, by ordering two or more products together you will get an additional discount (subject to the discount schedule presented on the order page).

 
Pro AudioUnit and VST plugins

Thanks.
 
I was actually interested in using this for individual tracks when reamping guitars.  The ability to take two different sources and have them fill the same space in the mix.

200bpm
Thanks.
 
I was actually interested in using this for individual tracks when reamping guitars.  The ability to take two different sources and have them fill the same space in the mix.

In that case, I think you''ll find curve-matching useful. Where it gets iffy is with program material. 

Harbal??

mixmkr
Harbal??

Yes, that's mentioned in the article too.

I use the matching EQ in Ozone a lot, but I usually apply it at less than 20%. 
 
The big advantage to me is in countering the inherent psychoacoustic difficulty of EQ'ing. More than other processing tools like compression, reverb/delay, imaging, and even loudness (limiting), I find it's very easy to lose my bearings with EQ and end up with something pretty weird by just tweaking without a reference. Bass boost.. ooh, that sounds good. High end boost... ooh, that sounds good too. Maybe a little more of each! It quickly gets to where what you've done sounds normal to your ears even if it's really screwed up. 
 
EQ matching helps you get back close to reality quickly. Of course, the choice of reference track is crucial. On the album I just mastered (a "reunion" record of my old band from forty years ago) I used the same song as a reference for every track, even though the songs varied in style a lot, just to gain a little continuity. That was Steely Dan's "Hey Nineteen", because it's immaculately clean, simple, perfectly balanced and not hyped toward any genre. If the record had been EDM or metal, that would have probably been a poor choice.

Like any other tool, matching EQ isn't a cure-all and can be badly abused. But I find it easier to tweak starting from a reference point than from a blank slate, because properly hearing EQ changes is so difficult.

+1 for Ozone matching, except I use the pink noise reference spectrum at 10% matching. It helps make all the songs on an album have a similar audio quality. As vanceen says, matching EQ is a guide, not a cure-all.