Here's one that seems to turn up here in Ontario FAR more often than it does in the USA where it was made. This is a white-glazed dry process U-47 embossed FEDCO in a circle on the dome, denoting the Federal Porcelain Company of Carey, Ohio.

This example is in VNM condition with no visible chips or cracks apart from the normal dry process porcelain crazing.

I'm asking $18 USD plus shipping for this piece. I'm always happy to trade for early Canadian glass or Canadian-made porcelain insulators. I accept PayPal, or personal cheque from any member of ICON or any collector with whom I have dealt before. Please feel free to contact me with any questions or for more photos, and look through my other items or unsold sales stock to combine shipping on items.