I have just search my silver. The silver that I have 1799 - has a different shield. So my 1806 silver is proberly the first in this patern.
This spoon is (grødske) is 37 cm and approx 1910.
It is made by Carl M. Cohr and the reason that I show is that my spoon is factory made. Please see detail.
So when I see your spoons I see a silversmith making them in the traditional way - compare that with my 1910. My spoon har the CMC mark - and the mark of a silversmith. But my "silversmith" has bought the spoon from a factory - adding his mark selling as his own production.
Yours are not made that way. I soppose that the shift - to factory was started after 1850 and in 1880/1890 the factories was dominating leaving the silversmith as more of a retailer.
My 37 cm spoon I bought January 3rd 2009 - and I have already regretted this buy. Empire pattern should be from that time - I will remember never to buy new again. Only from the original period.