What model of Oakleys are the Rudy Project Rydon's comparable to

Sunglasses are not cycling.

There is a few Oakley is u could compare these to.

First of all there r the Oakley Half X sunglasses, these r what the Rudy is probably look most like, here is the link.
http://oakley.com/pd/5220/17895
They r classed under 'active lifestyle' on the Oakley website, so r not designated sports sunglasses, but can be used for day to day activities as well as sport use.

However, if u want proper sports sunglasses that look like the Rudy's, then ur best bet is Oakley Half Jacket is with XLJ lenses, not standard lenses, here is the link:
http://oakley.com/pd/2081/10453
Granted, these do not have metal frames, but plastic, but still have a distinct similarity with the Rudy's. l have a pair of these & they r brilliant. l can wear them on the bike, off the bike, & on the beach too.

However, if u want sunglasses purely for cycling, go for the Oakley Radar's. l have a pair, & they r the best sunglasses for cycling without a doubt. They're brilliantly light, look awesome & the lens has a hydrophobic membrane woven into it to repel water, so u can see clearly in the rain!
http://oakley.com/radar
If u want cycling sunglasses, go for Oakley is without a doubt, they r fantastic. Their lens technology is miles ahead of anyone else's. Although they may be expensive, they r worth every penny!

l have both Radar is & half jackets & would recommend them both. However, if u want an esact likeness to the rudy's, go for the half x.

Hope this has helped!