TTW Audio make an external armpod.
http://www.ttweights.com/catalog/item/8679825/9981428.htm
Alternatively, you can go to any local machine shop and have a simple armpod machined out of any material you want.
http://www.ttweights.com/catalog/item/8679825/9981428.htm
Alternatively, you can go to any local machine shop and have a simple armpod machined out of any material you want.