I don't think Poland should buy foreign aircraft. Especially those that seem to be obsolete. EM-10 Bielik should be put into production. It's a low cost Polish military training aircraft prototype. It seems like the right choice especially when it contains stealth characteristics. Of course it should be re-modified with more modern aspects but it would seem as a good choice that the Polish people can be proud of.
http://en.wikipedia.org/wiki/EM-10_Bielik