Find a new supplier for stock (8)
I believe the answer is:
resource
This clue is a double definition.
'find a new supplier' is the first definition.
(re-source)
'stock' is the second definition.
(I have seen 'Stock of assets ' mean 'resource' so perhaps 'stock' could also mean 'resource')
'for' is the link.
(Other definitions for resource that I've seen before include "Possibility of help" , "A supply of materials" , "Reserve supply that can be drawn upon when needed" , "Available supply to draw on" , "Expedient - supply for use" .)