Product price matrix

For settings up the shop I'm working on I'm looking for an extension which adds the ability to define some kind of product matrix.
I need to setup products with a width / length and the combination of the width / length defines the price. Unlike the default options, this is a fixed price and not based on the base price. It's also an amount of combination with width & length that a single option with both and price won't do since the listbox will be way too long.

For example the following matrix:
- Width-- 80 90 100
Length
100 ---- 150 175 200
120 ---- 175 200 225
140 ---- 200 225 250
This small example would already create 9 combinations but my matrix will consist of a lot more lengths and widths.

Is there any extension so far that does this job or can help with the creating of my own?

I'm looking for exactly same module. I'm ready to pay for it around 20-30$. Thanks!