Right - it means 14 holes per inch. I used to cross stitch which is similar. They should have had that at the fabric store, I'm surprised they didn't. You can order online from Jo Ann fabric or Walmart if you don't want ot get it from ebay. But ebay is probably cheaper.

Sometimes you can get those plastic canvas in rounds - they're used to make coasters (remember when people used those lol). That would save you cutting them, if they're the right size.