Q: My product's size is an 8 ounce box. The unit doesn't list an 8 ounce box: can you add it please?
A: Because it's such a unique size, in cases like this we suggest that you use the unit field together with the unit description to fully describe the product.
The main idea is to tell your customers how many of X your price will get them. For example, list meat cuts by the piece rather than by the pound for those items that don't have exact weights. You want to avoid customers ordering 1 lb. of a broiler chicken!
Also, make it easy on yourself. You might sell herbs at $0.88 per ounce, but packaging random weights for multiple customers will get tedious. A better way would be to sell by the bunch, and use the Unit Description to tell your customers how many ounces are in that bunch. Then when harvest happens you can set up an assembly line for easy, consistent packaging.