How long should/could one stay in a foreign country after completing an MS there? Is permanent settlement abroad feasible?
You must figure out what's more important? A masters from US(top ten uni) or a permanent resident visa? As far as buying a property is concerned, that's no biggie, once you get a job.
Apparently PR is easily received in countries you mentioned Canada and Australia. Moreover, the education is not that bad out there. There are many good universities which are equivalent to or perhaps better than many US varsities.
On the other hand we have German universities which are deadly economical coupled with good academia. As far as I know Germany is the only country which also offers job seeker visa, which is enough to prove that the job availability is in abundance. However, language could be one barrier.
Hope it helps!