nfldraftscout.com has your man Leonardo Bates ranked #57 out of OT prospects.
They have Gaines and Marquardt as #22 and #23 respectively. That seems like 6-7th round territory to me.
Mr Bates will more likely than not be an UDFA. But hey, we've had some great luck with undrafted players!
"I think a lot of people might have looked at [post-Katrina New Orleans] and say ‘Gosh, I really want no part of this.’ For us, it was a calling. It was truly a calling. We felt like we belonged here and that we could do more than just win football games." ---Drew Brees