Ok in case you haven't herd I have rebuilt mine and got it playable. But heres a little guide on how you can make your own. granted its not cheap to do so (Unless you can get the shell of one) but they some how make certain games better to play than with a pad.
Heres a link to the guide
Note- I do not endorse usage of mame I recomend that you seek out some game packs for PC and use them on it.