New/corrected URL for history PDF in notes:
https://firstumusic.com/history/First%20Unitarian%20Chronological%20Building%20History%20Text%20-%202018.pdf
Unfortunately this is still all the information we can find for the 1828 organ.

This entry describes an original installation of a new pipe organ.
Identified by William Dunklin, using information from this web site: http://www.firstunitarian.com/history/FirstUnitarianChronologicalBuildingHistoryText4410_edted.pdf.
-- The First Unitarian Church of Worcester's 2nd building was constructed in 1828 at 90 Main Street. That building was totally destroyed by fire in 1849. The church records indicate an organ costing $2,000 was bought for this building and that the organ was lost in the 1849 fire. An E. & G.G. Hook organ was purchased for the 3rd building. First Unitarian's 1st building was built in 1791 on Summer Street. There is no mention of an organ in that building.