How do I create a special code for vendors?

We sell a baseball product and our goal is to have other baseball facilities sell it as well.

What we want to do is create a way for the facility to, when a customer of theirs goes to our website to buy our product, we can track that sale through a special code that the customer enters so we can then credit that facility and give them their due reward for send that sale our way.

Is there away to do this with Squarespace?

I hope this makes sense and I look forward to hearing from you soon.