Here's a zip with everything in it: [update: this is now a public pack]
http://www.alphaila.com/extras/interface_pack.htm
This shot below shows what the Gunreal interface looks like. (though, of course, you can build whatever kind of interface you want) Click here to view it full-size, and watch the Gunreal trailer to see the buttons being pressed, etc. (btw, ignore the upper-left clock icon. That's from UT2004)

And, since specific usage terms are important to devs, they are:
You can use/distribute this pack freely with any Spring project, including if the project ever goes retail (and including any derivative of the project, even if it's from scratch). No payment or permission needed. If giving credit is highly inconvenient, for whatever reason, you can leave it out. Last, you can edit the textures/sounds/etc freely, to make them fit your stuff.