A tiny store specially designed for office materials (10)
I believe the answer is:
stationery
'office materials' is the definition.
(pens, pencils etc)
'a tiny store specially designed' is the wordplay.
'specially designed' indicates an anagram (I've seen this in other clues).
'a'+'tiny'+'store'='atinystore'
'atinystore' with letters rearranged gives 'STATIONERY'.
'for' acts as a link.
(Other definitions for stationery that I've seen before include "The papers, etc" , "Materials needed for writing" , "Treasury tags, for instance" , "Various items in paper" , "Writing paper, etc" .)