Plastic Shipping Bags import to Belgium

I am contacting you for information regarding plastic mailing bags.
I run a company that sells on amazon, and I would like to launch this type of product.
I would like to know if you create plastic bags with these dimensions: 17*24cm, 20*30cm, 25*35cm, 35*45cm.
If yes, is it possible to have information about your prices according to the ordered quantities?