Top rate protection for new heir apparent? (5,6)
I believe the answer is:
crown prince
'heir apparent?' is the definition.
(I've seen this in another clue)
'top rate protection for new' is the wordplay.
I cannot quite see how this works, but
'top' could be 'crown' (crown can mean the top of something) and 'crown' is found within the answer.
'new' could be 'n' (common abbreviation eg NT for New Testament) and 'n' is located in the answer.
The remaining letters 'price' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
(Other definitions for crown prince that I've seen before include "who may be expected to succeed" , "principal heir" .)