Back when banjo ukes were very popular ('20s-'30s), the Soprano size was the standard (hence the Soprano's alternate name, "Standard). Occasionally, you'd see some Concerts here and there. Your best bet would be to get a Gold Tone Tenor Banjo Uke, or depending on your price range, a Beansprout Tenor Banjo uke. If you're willing to go down to the Concert size, you have a few more options (AnueNue, Lanikai, etc)