Manaaki has a partnership that is currently offering free eCommerce websites, I’d recommend checking that out to see if it’s suitable https://www.manaaki.io/1000websites/
Before diving into who is the right manufacturer, it’s crucial to get a very clear understanding of who your target customer is, what their needs are and who your competitors might be. One company that comes to mind is https://ohnatural.co.nz/product-category/new-zealand-made/
It’s important to differentiate yourself so customers know WHY to buy from you and not others.
Once you have a good understanding of what ‘niche’ you are targeting and the value you will offer them, that should help narrow down what type of products you want to offer them. (If you have this already), I’d recommend researching all the different types of NZ manufactures you think are suitable and contact them about your proposition. I’ll comment back here if I find a good resource to track them down.