Yes, but the AMC for MA803 states.
1. The pilot–owner should hold a valid pilot license issued or validated by a member state for the aircraft type being maintained.
Now my understanding of that is as the NPPL is issued by the CAA then it should be OK, but the potential CAMO I spoke with is not sure that is how EASA will see it.
A very nice site for getting to grips with part M which is much clearer than the EASA or CAA web site can be found at
easyEASA home page, english, EASA part-M regulations in an easier to read format there is a version there incorporating the proposed NPA 2007-8 changes.