Forum Academy Marketplace Showcase Pricing Features

Best method for table pricing? Price breaks for higher quantities

I have an item that will mostly be sold in portions.
I want to let buyers maintain a table of pricing and offer discounts for higher quantities bought.
I also want to offer a standard pricing model that would default and seller can customize if they want
1.0 = 1.0 * x
0.5 = 1.15 * x
0.25 = 1.22 * x
And so on.
Would that price table be its own data type?
Is there a plug-in for this?