07 imprezza roof rack?

hey folks. my girlfriend just bought a kayak. she owns a 2007 imprezza. I noticed on the top there are removable "plugs" of some sort that have two threaded holes below them. I assume these are for a roof rack. the problem is that i cannot find a kit that utilizes these factory installed mounts. I have tried to notice other imprezza's with a roof rack and have not seen one yet. I have seen the clamp type but would like to avoid that style. any help would be appreciated.

This is may be not the best solution but dealers usually carry all the necessary stuff. I bought cross bars for my Forester at REI when it was on sale for $15, but I already had the bars installed from the dealer.

Good luck,
Sam