I got my newest eBay purchase in the mail today: The Christian Helper; or Gospel Sermons for Congregations and Families "issued by direction of the General Convention of Universalists" in 1858, and printed (of course) at 38 Cornhill, Boston.
This was "a Second Volume of Sermons for the use of Societies, without minister, of unorganized circles of Worshippers, and of Private Believers generally." This was part of the Universalist missionary effort, and would have been used in worship (if used at all) with something like the Gospel Liturgy.
Here's something I didn't know about these resources: it is dated. There's a sermon for every Sunday for the first half of 1858, and the sermons feature some top-flight preachers. The whole effort seems to have been compiled or supervised by "A. A. M.", none other than Alonzo Ames Miner, Universalist minister and second president of Tufts.
I'll have to find a good sermon and type it out for y'all.