Material obtained from dollar sign (7)
I believe the answer is:
buckram
'material' is the definition.
(buckram is a kind of material)
'dollar sign' is the wordplay.
'dollar' becomes 'buck' (synonyms).
'sign' becomes 'ram' (I've seen this before).
'buck'+'ram'='BUCKRAM'
'obtained from' is the link.
(Other definitions for buckram that I've seen before include "Coarse material" , "Coarse stuff" , "stiff stuff!" , "Bookbinding material - cub mark (anag)" , "stiffening" .)