I don't think the Stella Alpina will be happening again, the local government have now closed it to motorized traffic at weekends and local environmentalists have remodeled the top of it somewhat
There are, however, plenty of similar trails through the whole Alpine area.
As for similar Rally's I've seen a few covered on ADVrider.
For my week long getaway this year I will be covering the four geographically extreme points of Ireland coming back via a spin round The Isle of Man TT route.