Natalie:
Another route for investigation is through the American Board of Commissioners for Foreign Missions (ABCFM). Although missionary activity ultimately spread throughout the entire Pacific rim, its musical influence only extended into Hawai'i and other Pacific islands, and China, with words-only hymnbooks being published in a few other places. The types of sources printed and used by missionaries would give some clue as to the possibility of an American tunebook named
The Sacred Harp being used throughout the Pacific Ocean. Hawai'ian sacred music imprints begin in 1834 with Hiram Bingham's
O Ke Kumu Leomele published in Honolulu. Predating your reference by three years, none of the tunes in this collection draw from any contemporary publications titled "Sacred Harp." In 1840, Milo Calkin, J. F. B. Marshall, and F. Johnson, a group of local merchants in Honolulu, published their own tunebook,
The Hawaiian Collection of Church Music. It did draw heavily from Lowell Mason, but only from one of the editions of the
Boston Handel and Haydn Society Collection of Church Music. Although not done under the auspices of the ABCFM, it influenced later missionary publications such as
Ka Lira Hawaii (The Hawaiian Harp), which went through three editions beginning in 1844.
The first shape-note publication originating from the Pacific that I've come across is also later, appearing sometime in the late 1870s, in this case in China.
Kai Ge [Triumphant Song] (Fuzhou City: Meihua Bookstore, 1879), originating near Taiwan, was published in seven-shape notation and resembles somewhat contemporary seven-shape publication activities in Philadelphia. The repertory consists of Lowell Mason Sunday School material and early gospel music. Thus, it does not resemble earlier works before 1850.
Based upon the evidence, I think the case for a collection of devotional poetry from a publisher in the United Kingdom would be the most likely candidate for your referenced source. Shape-note notation was not found in the Pacific rim before the 1870s (at least from surviving sources). Lowell Mason's publications did exert some influence, but not
The Sacred Harp. You might check the Grove dictionary of Australian music. It has an article devoted to psalmody and hymnody I believe and would give you some possible avenues to explore should you choose to look further into this subject.
Good luck.
Nikos Pappas, Lxgtn