Rob when I purchased my BF Hub & Ring....I got the 2.76" & 2.93" ring (you CAN only buy for Ring if that's all you'd like-get the 2.76" IMO)
Here's the $$$ from there site
Hub and 1 Pulley Ring (Non-Slip S/C Pulley) $149.95
Hub and 2 Pulley Rings (Non-Slip S/C...