I'm not familiar how the original you referenced was made but here are some thoughts. If it was originally cast, I would just start with solid brass rod, turn the shape and silver braze a tab on. If it was originally formed from sheet, I would do the same. In this case, you will have to swedge the bell shape and will have to start with thick enough stock to get the bands filed on. For all the hastle trying to purchase one, think you will be better off making it.