Hey DusT,
You can find a circular foot for these with thread. It will have three holes for screws, so you can screw it at the top of your case. I can think of a few other way to attach one, but we’d be getting into do-it-yourself country.
I can’t speak for this particular make/brand of gooseneck and of course it depends on your mic (hoping you won’t go for cheap b.t.w.), but they should be able to hold up your microphone, yes.
Finally, if you get a condenser, with a gooseneck with xlr at the bottom (like the other link I posted), you can use something like this:
http://www.bax-shop.nl/phantom-power-supply/behringer-micropower-ps-400-compacte-fantoomvoeding/product-details.html
It will provide phantom power to the mic. Price is decent at 25 euro. You can surely find a place for it in your coffin/flightcase. It WOULD look real clean as you won’t see any cabling going.
Greetinx.