We do not catalogue and sell any speedrings or softboxes for the T2, but Chimera does. I found a 245mm speed ring on their site, using their Speed Ring Finder tool. https://chimeralighting.com/product/spe ... b3-245-mm/
In general, Chimera ought to be able to help you out with purchasing that speed ring and the appropriate soft box to go with it.
Brian Doran
Product Specialist, Lighting
ARRI Americas