WPLab - Bulk Pricing for WooCommerce v1.8.1
Offer quantity discounts on your products the easy way. This plugin will enable you to set up bulk pricing rules for single products or whole categories with just a few clicks.
Create an unlimited number of discount rule sets and choose from those predefined rule set when you edit a product. Or define individual pricing rules directly on the edit product page - or use the built in hierarchical categories page where you can assign rule sets for all your product categories on one page.