Custom content problem

Hi everyone

I have been searching through plugins and websites all day looking for a solution to my problem but with no luck.

I am building a theme based on the Roots boilerplate. The client wants 3 boxes under the main content where he can put content in. (Text and images). But he prefers if he 1) creates the content 2) saves it as a page or post and then 3) on each page be able to select the posts/pages from a drop down list. That means there should be 3 dropdown menus, so he can mix and match from all the posts/pages.

Does anyone have a suggestion how to accomplish this. Or would I have to build a plugin myself? (That’s gonna take me a while ??

Thanks

Janus