That spare Platinum I got, I bought on Ebay from a company in Canada >.>
And you can check what other nature the spread comes in 2 ways:
1) With PokeRNG, when you get to nature, type in something like 'a' or 'asdfajow' and it will search all natures so if you know the IV's, you can do a search and all the natures it comes in will be returned.
2) With JavaRNG, it works basically the same except you can search Method J and you don't have to type in 'asfjwovw' as there is an 'ANY' nature option; just make sure that you pick 'SAME AS SPREAD' for the synch thing at the bottom. =D (I usually use JavaRNG now anyway because of the Method J option)