I just checked EuroBillTracker Diffusion charts & over 44% of 10 Euro notes have been reported from Austria (10% NC) & Germany (34% WA) prefix. For the 5 Euros, the distribution (# of prefixes reported) is about the same: over 40% of notes come from either Spain (24% for VC prefix) or Portugal (19% for MA prefix). So your toughest note is the 1st TEN pictured with NC prefix.