At the time that the ramshead designs were most popular, harps were single action. There are a very few early double action harps with that kind of ornamentation, but Erard (the maker of the majority of the surviving harps from that period that you see in the US and UK) needed to alter things because column capitals got longer to accommodate the wider action plate necessitated by the extra row of discs on a double action mechanism, and also styles were changing, too, starting to move away from the extreme simplicity of the early Empire period, just as the Empire styles were a reaction against the more extravagant styles of the 18th century (when elaborate scrolls were the thing).
The most popular early motif for Erard double actions was the so-called Grecian design, with a row of Nikes (the winged goddess, not the shoe) around the capital:
http://www.hbryan.com/restored/bigkirihrp.jpg
This in turn was followed by the famous Erard Gothic design (for the larger double-action harps which succeeded the Grecian), very much in tune with the trend for all things gothic in the early Victorian era.