Design aid — tool that draws street for page (7)
I believe the answer is:
stencil
'design aid' is the definition.
'tool that draws street for page' is the wordplay.
I cannot quite see how this works, but
'street' could be 'st' and 'st' is located in the answer.
This explanation may well be incorrect...
(Other definitions for stencil that I've seen before include "office plate" , "It's perforated for ink or paint to pass through" , "Aid for drawing" , "Cut-out master pattern" , "Model" .)