I would imagine that it may be hard to find something which matches your existing and not just fairly close.
How many do you have to make? As indicated you can mostly likely find a rosette cutter for the center. You may well be able to find one or more cutters to create the outer circle and use a trammel arm on a router. The petals are made with a gouge of the correct size, fairly simple to make. For the plinth block a few could be made rather quickly using a combination of a tablesaw, a carcass saw, a gouge and block plane.