Hi again.
I do have an idea for 19d, likely wrong, but here they are anyway ...
Two words (5,5) ...
For 'IT', think Tara Parker-Tomlinson, Tamara Beckwith etc ...
Whole answer = something to help them navigate while shopping.
To repeat .. I may be barking up entirely the wrong tree with this; if so, apologies for timewasting.
JimC