Pour very shakily for dealer (8)
I believe the answer is:
purveyor
'for dealer' is the definition.
(someone who sells or purveys something)
'pour very shakily' is the wordplay.
'shakily' is an anagram indicator.
'pour'+'very'='pourvery'
'pourvery' with letters rearranged gives 'PURVEYOR'.
(Other definitions for purveyor that I've seen before include "Supplier of provisions" , "Provider (of goods)" , "Retailer" , "Supplier of victuals" , "Supplier (of food, etc)" .)