There are a few different places to look for replacement parts for your tile removal tool. Your first best bet is the store where you purchased the tool. They may have a section dedicated to replacement parts, or they may be able to order them for you. Another option is to search for online retailers specializing in power tools and accessories.
A quick search should reveal several options. You can narrow down your results by selecting the correct model number for your tool. Finally, you can check with the manufacturer's website. They will have a listing of authorized dealers where you can purchase replacement parts. With a little bit of effort, you should be able to find the replacement parts you need without any trouble.