Not sure if this should be a feature request or go into 'Tag/Wiki Projects and Questions'.
To start with, sources linked to in source:*inkbunny.net/files* used to work, but now you probably want US/TX.ib.metapix.net domains if those are detected to be 404'd. Many tools/sites use servers located in the USA, so won't work with the NL1 and related subdomains.
I'd consider looking into source:*inkbunny.net/files/screen/* and other similar paths, and seeing if the full resolution was actually uploaded, too. It's quite possible that some fell through the cracks. It 'feels' like this could be mostly automated, so it's kind of a feature request as well.
Testing them for 404 status would also make it possible to get a list of dead URLs for the appropriate domains.
There's plenty of other sites that belong in this topic, I bet.
:edit:
Wait, some work for inkbunny.net domain? Sigh, this is frustrating. Ones that weren't working seem OK. Derp, probably ISP/DNS issues.
Updated