I've looked around and I must be missing it somewhere... so sorry if it's really obvious x.x OTL

How much is it to make 1 batch of 10 of a particular CW?

Go to http://subeta.net/explore/custom_clothing.php (to navigate there from menu: Cash Shop > Custom Wearable > Create CW)

Scroll down to the form and click on the "Type of Item" dropdown and it'll show the price for a batch of a certain item type.

Thank you! I was able to find what I needed. :)