The only way to acquire older/one time models is the secondary market, like Blade Forum Exchange.

I believe the Mud Puppy was a one time deal here so good luck <img src="/ubbthreads/images/graemlins/wink.gif" alt="" />

We usually never know "exactly" (exact date) when any blade will be released or in the store, just keep checking for it often! you should be able to get one <img src="/ubbthreads/images/graemlins/smile.gif" alt="" />