David, putting a price on something like this is always going to be difficult, it is with any sort of art but you could start by pricing them as a normally manufactured item & if your happy with what that works out to then sell them at that & if your not because it is artistic then add a bit more on.
You might have to bump your labor rate up a bit though as your working from home & won't have a lot of the usual stuff required to work out a labor rate.
As for the design & toolpath creation side of things if you intend to stick with 10 of each piece then just divide the time it took by 10 to give you a price for this part of the process that you can add to the other costs.