I cant tell what brand yet, but its definitely an older (80's/90's-era) Offset-Chassis variety of racekart that was specially designed for competing on oval tracks.
It's definitely not the Sprint Kart/Strait-Rail variety that are designed for racing on tracks with right & left turns, If that's what you were expecting.
Most all parts from other brands should interchange on yours just fine, except the front bumper and spindles.
I used to race oval karts and could help you source parts if you wanna post a list.
Might be able to save you some bucks on shipping cost if you included your location too

---------- Post added at 08:00 AM ---------- Previous post was at 07:25 AM ----------
After closer study, I've noticed some design features very similar to the older Coyote brand models. You could take a couple more detailed pics and try emailing them to their website. Also check closely for it's frame #'s and include those in your email when asking if its one of their older models.
Here's their contact info:
http://coyotekarts.com/contact/contact/
PS:
Be sure to include that you wanna buy parts from them!
They probably get a 100's of kart-I.D. emails like this, and would hopefully try harder checking with their older employees that would remember the older models, if they realize you wanna buy parts...