exhaust manifold gaskets....

[dominoy2k1]

ok here is what happened, when i removed my manifold i noticed the gasket was cracked an i was having a leak...my question is since i can only get the gasket at dealership is there any other way i can make the gasket? also would there be any problems if i keep using the cracked gasket for a bit longer?....all answers are appreciated, not really only the good ones, but still...please help...