It would be better to have a working PC than one that doesn't work. With it not working, you can't test almost anything and will be way past the return window.
As for your budget, I'm assuming that's for the PC and not a specific part. Just one question, is it 1500 EUR or USD.
As for shipping from the USA, you will be hit more than just with customs. Shipping will most likely cost tens just for something small and will probably cost >100 just for a big part, like the case.