Trever: in case you didnt know Wilton made that same vise for Snap on so you can buy a snap on sticker for it if you like that brand better. Nice find and no little thing either so should do most any job you need a vise to do. Im guessing you didnt pay much for it but i think a new one costs about $500 somdont abuse it and pass it on to your grand kids.
Part number for the lower pipe jaws is 2904200. There are a number of places to get them, such as ereplacementparts.com where they are priced at about $30.
Search around the web and eBay for the lowest price.
Found a date stamp of 12/86 on the bottom. After reading several threads I'm a little worried this vise might not be us made. My new wilton 1765 has made in the usa cast into one side and this 1760 doesn't any chance it's from china?