I have wee feet - 26.
I have other Garmont boots in 75mm also so can keep touring on those but it seems that the NTN range of boots don't have a Kenai equivalent.
I will need to do more research on the duck bill but from a quick look there doesn't appear to be any metal there.
This is the sole: [
imagecdn2.panjo.com] and you can see the space for the NTN insert.