This is not Rusticana - there are a few differences. A while ago I was looking at this pattern but could not find out who the maker was.
I also would like to know where to get tops for these too! Occasionally you will find odd ones at flea markets and the like, they seem to have made them in many sizes, often differing by only an eighth of an inch or so. I have several spares picked up over the years - If you are lucky maybe one of them will fit - what is the outside diameter of the rim of your vase?
John