on its way from the bay, and no it is not a dress
Sellers pics for now and this type was introduced toward the end of the Victorian period and phased out early in the 20th century. It has regimental buttons, probably silver plated, but is sadly missing its shoulder straps. It is an officers service tunic worn prior to the introduction of the Khaki SD uniform in 1902 and is as the title suggests correctly called a Scarlet Frock, as opposed to the more commonly seen tunic, which later became known as the parade/dress tunic. It does give me an example of 3 of the uniform tops from this period, this one and one each from circa 1910 for the Welsh and the Hampshires -see attached illustration of the types used.