I'm actually not too worried about the OL... as of right now at least.
You've got 2 starters locked in with Stanley and Linderbaum. I've been approaching it all offseason that at least 1 of the G spots is going to be occupied by a younger guy, probably Cleveland in this case.
That leaves 2 open OL spots at LG and RT. Neither is barren although there are some big question marks still. RT you're probably looking to add but have a known solid option in Mekari and a guy that has had moments in Faalele as fallback options. LG you have Vorhees and Sala who are complete unknowns but still options.
All in all, you're probably looking to add 2 starter-ish guys either via the draft or FA, but you aren't dead in the water if you can only get 1.