Here is the plot: two girls who didn't have horses and didn't know how to ride go toa local farm/show stable, and someone there taught them to ride and later they rode in horse shows for this farm. I remember the names of some of the horses... Latest Vogue, Captain Dan, King (something) and there were also two ponies that they rode (don't remember their names). I read this book in middle school, so around 1970-1973? Thanks