The "eleven dozen and seven" is functionally no different from "One hundred and thirty-nine." We'd just have 2 more characters than we do now.

We even have a name for a third digit in base-12. 12 dozen is a "gross".

The Babylonians used base 60, which is neat because it cleanly divides by 2, 3, 4, 5, 6, 10, 12, 15, 20, and 30, whereas base 10 has just 2 and 5.