The requirements aren't that intense. It's just a matter of who they select. You can check www.nomi.navy.mil . .click on NAMI and check physical reqs. Want to be able to do 225 PFT (also avail online). 2.0 GPA and the test score reqs are the same as the Navy.
The question is what does it take to get selected. Any recent selectees have any comments? Find an Officer Selection Officer and pick his brain (and start application process). They're there to find potential aviators (well, Marines). ..
Yes, you can get an aviation guarantee. Just got to have what it takes to handle OCS. . . and ultimately to be a Marine. Good Luck.