Thanks.
The SAAMI standard can be very helpful when shell length is of significance:
http://www.saami.org/specifications_and_information/publications/download/209.pdf
Do you have a link? I found Remington slugs at http://www.ammunitiontogo.com/product_info.php/pName/100rds-12-gauge-remington-buckhammer-2-34-1-14oz-slug-ammo, but no RIO rolled crimp 00 buckshot.