Shelton and Goldblatt 'Country Music Story' have a photo of a group by that name on the Opry in 1930s. Unfortunately, the personnel are identified only by knicknames: Sleepy, Slicker, Hungry, Dynamite, Robbins, Irontail and Sherriff. Malone 'Country Music USA' refers to them as a California group by the name of Sherriff Loyal Underwood's Arizona Wranglers - that accounts for the 'Sherriff'. The French label, Fremeaux & Associes, has a double CD called 'Western Ballads and Songs 1925-39' divided into 'authentic cowboys' and 'Hollywood cowboys'. Included on the 'authentic cowboys' CD is the Arizona Wranglers singing 'Stawberry Roan'. There is a spoken intro by someone identifying himself as 'the Sherriff' and referring to the singer as 'Nubbin' - it is probably the same outfit. However, the performance is a solo effort with the performer identified as J.E. Patterson - recorded in Phoenix Arizona 1929. That's all I can find at the moment. Hope it is of some use.

Stewie.