I think Ron is probably right. The reverse type may very well be the seated goddess Ardoksho (the pic is upside-down). I believe that both Kanishka II and Vasu Deva issued small bronzes with reverses like this...although my disclaimer here is that I'm just starting with Kushans 
Some examples for comparison:
http://www.vcoins.com/en/stores/nem...Default.aspx
http://www.anythinganywhere.com/com...ma3522-1.jpg
http://www.anythinganywhere.com/com...3523v1-1.jpg
Some examples for comparison:
http://www.vcoins.com/en/stores/nem...Default.aspx
http://www.anythinganywhere.com/com...ma3522-1.jpg
http://www.anythinganywhere.com/com...3523v1-1.jpg






















