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So we've just got Challenge Rating, weight and some descriptive text to work out.
They look Challenge Rating 10 to me. They're certainly at least a CR stronger than a CL 8 Efreeti, but I think their spell resistance and nastier SLAs (especially eyebite, resilient sphere and wall of force) is enough to make them 2 CR tougher, although I could see a case for a "strong CR 9".
Their "anti-oathbreaker" special abilities shouldn't count for the CR, since they are unlikely to apply to a standard encounter.
As for weight, scaling down the 2000 pound 12-foot SRD Efreeti to 9 feet works out at ... 843 pounds!
Typos? I don't make typos. They're deliberate errors to check whether you're on your toes.
The Oathbinder's got a "10fold or hundrefold" in the paragraph above its height & weight which looks like it should be "tenfold or hundredfold" and it's still got a question mark in "Alignment: Always lawful neutral?".
Apart from that I think we're good.
I vaguely recall we talked about giving it a racial bonus to Sense Motive or Diplomacy, but its skills are plenty good enough as it is.