Since it was built in a country that uses the metric system, makes sense to me. I don't know about SoCal, but you should give McBeath Hardwoods up in Berkeley a call. I think they have an affiliate over in Arizona that carries teak as well. You may very likely need to have someone mill it for you to fit your specs. Maybe consult the GB owners forum too.
"There's the Right Way, the Wrong Way, and what some guy says he's gotten away with"