@Super Werty the photo link is broken, so I'm not sure what items were pictured, but does this include the ARP bolt and/or MMR support washer or anything else? Or is it just the TSS OPG and MMR Sprocket? If it's just the gear/sprocket only, the price seems to have dropped from $675 when you purchased them to $556 from the same vendor (Beefcake). Nothing wrong with your asking price, just wondering if I'm missing some extra included bits that may have been pictured but not mentioned in the text.
What's are the differences between the base-level Boundary stuff, the mid-range MMR stuff, and the high-end TSS stuff? Cryo treated? Different alloy steel?