Your best bet might be some generic m5 shims configured to your needs.
He prob wants to use shims between he inner axle races to prevent them from compressing together.
Some of these to fill the big space
http://www.tqrcracing.com/shop/product_view.asp?p_id=10700
Add these to fine adjust
http://www.tqrcracing.com/shop/product_view.asp?p_id=9155