My money's on Thomas Dicks. The work of his that I've seen is all concentrated around this time, and his is the only mark I've seen with a pellet between the letters.
Jackson's seems to think that the last mention of Thomas Daniel was in 1784 although I've seen a piece purporting to be his from 1788; either way, it's slightly early to make it likely that this piece is by him, though still possible.
A very nice item by the way.
I've included pictures of their marks.
Miles
Thomas Dicks
Thomas Daniel

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