I bought this online for use with my B2601:
Husky 3/4 in. Bow Shackle in Black
https://www.homedepot.com/p/Husky-3-4-in-Bow-Shackle-in-Black-54537/312967053
When it arrived the pin is too wide to fit in the drawbar hole. My tape measure makes it look like it is just a smidgen over 3/4", but...