Where can I buy unsweetened shaved coconut?!

I need it for a low-carb key lime pie recipe that calls for a coconut crust. I looked for it at my local grocery store, but all they had was sweetened. So I bought a whole coconut and figured I'd use a cheese grater or something to shave it myself. But it was a total pain to get the coconut off the shell, and once I finally managed it turned out to be rotten. I ended up making a crust out of butter and almond flour. But then the crust completely crumbled apart. It would have been easier to screw the crust and eat the filling like jell-o (it was a refrigerated pie based on sugar free jell-o and cream cheese). So where can I find unsweetened coconut to make a proper crust this time? I could buy a whole coconut again and hope it's not rotten, but besides being rotten it was a total pain to crack open (I tried several methods before finally just whacking it with a hammer...not exactly the most elegant method of making pie, but more effective than anything else) and like I said, a pain to pry off the shell (piece by tiny piece I pried it off with a spoon. It took ages to peel half the coconut, which is when we discovered it had gone bad). So where can I find simple, ready-made flaked/grated/whatever unsweetened coconut?