Amazon, eBay and independent pipe shops are all sources of replacement pipe stems. Independent retailers who sell pipe stems include Pipe Makers Emporium and Briarville. Both Pipe Makers Emporium and Briarville make their pipe stems to order and offer a wide selection of colors.
Modern pipe stems are made from acrylic or hard rubber. The acrylic used is sometimes called lucite, while the hard rubber is also referred to as vulcanite or ebonite. Acrylic is more fragile, but comes in a greater variety of colors; hard rubber is less susceptible to breaking, but comes in few colors and is prone to discoloration with use.