Copper Bays, Flashings, Gutters and More, INC offers a selection of many types of finials. Custom mounted on any roof at any peak. We recommend for best balance to use odd numbers (1,3,5,7).
The details matter...
Beware of other installers who fail to mount the finials at true 0 degree angles. What may look strait from the front, would look crooked from the sides.