I've created a new block for the marketplace that allows you to undelete pages you've deleted from your concrete 5 marketplace. It's called "Recycle Bin" and you can learn more by reading the rest of this post.
I'm not sure what happened to the first post that I made about this, apparently I deleted it or something. Oops. But google has cached this page so I'm recreating it...
Recycle Bin is an add on for the concrete 5 marketplace that modifies the way that pages are deleted. Instead of the page being removed from the system immediately, it is first moved to a holding area under a "Recycle Bin" page in the dashboard. From here you can choose to delete the page permanently or restore it to a location on your site. You may choose if pages stay for a certain number of pages (say, 30 pages max in the recycle bin) or days (keep pages for a number of days.)
Pages are still visible to page search while they are in the recycle bin because they aren't deleted, but they do not show up in the standard site map unless you choose 'display system pages' and then drill down through the dashboard to the Recycle Bin / Deleted Pages node.
This add on was recently approved and you can now download it for $15.