Not, shall we say, easy, easy but certainly doable.
The data for avatars is held in the ‘sfmembers‘ table in the ‘avatar‘ column. But, it is held in a php serialised array. For an uploaded avatar this takes the form of:
a:1:{s:8:”uploaded”;s:19:”yellowswordfish.jpg”;}
The problem – in case you do not know about serialised arrays – is that that number after the s: and before the file name, is the count of the number of characters that make up the data portion. Hence – ‘yellowswordfish.jpg’ – s:19 – representing a 19 character string of text.
The ‘sfmembers’ table is keyed on the user_id by the way.
So the main problem would be formatting that data for each individual…