The "rubber" you are talking about sounds like what we call a "Hi Start" and this is heavy duty one
http://www2.towerhobbies.com/cgi-bin...?&I=LXE636&P=7
I don't know what one would cost in your area. You could make one yourself if you have access to a surgical supply store and can make your own parachute.
There is also a smaller version that might work and is much cheaper.
http://www2.towerhobbies.com/cgi-bin...?&I=LXE638&P=V