Tundra deck rails

I think I have a full set of rails somewhere and I have definitely have a full set of tie down cleats still in their plastic with the cardboard backing. I think I have another set somewhere (you'd understand if you saw the state of my shed). I may have more than one set of rails too.

(EDIT: I think I took off my rear rail when I installed my cover, so I have that by itself too)

 

My SR came with a well loved (beat up) spray-on bed liner and no deck rails, so I am definitely looking to improve my situation back there. I don't mind the bed being beat up, but I'm liking this thread for rail ideas. Unistrut is something I am going to look at, but otherwise is there any reason OEM deck rails wouldn't snap right in? I'm curious why the Toyota Parts store says the spray-on liner must be ordered with the deck rail system?

 

That seems odd (I checked Sparks Parts and they do not have this note). Likely this note was added because if there is no bedrail then the installer will just spray bedliner over the mounting holes. I had my spray-on bedliner added after several months and the installer removed the bedrails and then marked the holes so they would not get filled with bedliner.