I get mine with my sausage making stuff at The Sausagemaker
Or you can make your own:
MEAT CURES - DO-IT-YOURSELF
PRAGUE POWDER # 1 or INSTA CURE 1
This mix is not normally used in fresh sausage. It can be used in “cured
sausage” that is not fully dried.
1 pound of Kosher salt
1 ounce sodium nitrite Thoroughly mix the salt and sodium nitrite. Uneven mixes will result in too
much sodium nitrite in some parts of the sausage and not enough in others.
For each 10 pounds of meat to be used in the sausage, add 2 teaspoons of
Prague powder # 1.
Unused Prague powder #1 can be stored in a dry jar.
Note that the Prague powder # 1 is dissipated after about 2 weeks making it
unsuited (as the theory goes.) for long cures.