10 x 70 mm Ruby Ball Tip
Buylink:
http://www.shop.emicroscribe.com/product.sc;jsessionid=6F29DACA9EB4C7C9D756BC03B9250B94.qscstrfrnt04?categoryId=14&productId=112
Cost:
$188
Summary:
Dia ..3937" ( 10 mm) Length to center .2.7755" (70.5mm), Delta offset -1.9881" (-50.510mm)