Tim, the purpose of the ENUM data type is to allow you to specify a list of legal values. Putting anything into the database that isn't on that short, defined list is an error. That might sound like it's appropriate for what you're trying to do ... but it's not.
If I understand the original question, you're jumping into the deep end of the pool without learning how to dog paddle first.
You have objects for sale that can be obtained from more than one supplier? And presumably one supplier sells more than one object?
This is a data modeling problem, and you need to understand how to design database tables before you start writing code.
There are a lot of books and tutorials on the subject. I typed "relational data modeling" into Google and found the following link, which looks very good:
http://www.utexas.edu/its/windows/database/datamodeling/rm/overview.html