Yes, I agree with the latest consensus...'tis the ubiquitous Style 1.
Just kidding, powgor. It's still a lovely ukulele. And valued. The date range is much wider since it is a style 1, as Martin used wooden pegs on them for a wider span of time; until 1927, to be specific. But, as jimhuang and mattyukeaholic note, still 1920s and still super sweet. The crack should be repaired, and a luthier could clean it up and do a nice job for you. I'm guessing, what, $150--crack fix, set-up, clean-up? I'm asking others here, I don;t know.
I yanked out "the book", and 1920-1927 Martin Style 1s: total production (not including Ditsons, Wurlitzers, blah blah; just Martin branded style 1s):
13,017.
I'm always amazed, when I look at these charts, how many style 0 and 1 ukes Martin made, relative to Style 2s and esp 3s. Interesting.
Anyhow, it's almost 100 years old, powgor. And with 100 years of house fires, floods, ex-husbands and fans of The Who, it's a mystery how many of those still exist. It's a keeper! Thanks for sharing.