Harris and Harrington, a US retailer did not manufacture clocks to my knowledge. Instead, H & H was an importer.
Without having the clock in hand for inspection, I cannot positively state the origin of the case or its movement, or the face. Your single snapshot photo offers no evidence to assist in any reasonable or conclusive answers.
The mahogany case dimensions you provided, 15" by 11" and the spacing of the two winding holes in the dial suggest a small round French roulant or similar US made movement.
My comment(s) were based on visual perusal of your snapshot image. The artistic style of the wood case with flowing symetrical curves are generally found on attempts that later became known as Art Nouveau. The abrupt upward peak is a style that was not admired in the US during the period H&H prevailed.
More and detailed photographs might provoke more a more positive reply.
The movement is a typical round French type, signed 'Vincenti'. Besides the Harris & Harrington marking, it's also marked 'Made in France', which I gather dates it post 1890 which coincides with a H & H clock. Is it common to see Vincenti movements in clocks this late, seeing that they shut down manufacturing in 1870 ?