multiple item codes same item

Hi List.
I am hoping someone out there can point me in a direction.

We currently have a product for our example lets call it ABC we buy this
product from 3 vendors. In order to track costs and different package sizes
we currently have multiple item codes on the system for it.
We will put the package size and the vendor into the item code. But really
they are the same physical item.

So it would like this:
ABC-55CE
ABC-55GL
ABC-16BBCE
ABC-16BBGL

We are now running into a lot of issues with this. We are looking for a way
to streamline this into a way we can just have ABC in the computer and then
select the package size and vendor instead of making them part of the item
code.

Any help would be appreciated. Thanks!

Jeff Williams