Ernest Tubb - Thirty Days (buy)
Early rock'n'roll owed a lot to country music. And vice versa. Take this Chuck Berry hit from 1955 (#2 on US R&B chart), replace Chuck's vocals with Ernest Tubb's, replace Chuck's guitar with Billy Byrd's (not to mention "Half Moon" Bradley's* piano and Tommy Jackson's fiddle), and you've got yourself a great country record.
* Tubb jokingly referred to producer Owen Bradley as "Half Moon" because he only played halfway like Moon Mullican