Suitable project for OSCommerce?

[Forsooth]

I'm researching a project that will provide a similar service to this site:

 

Carbon Passport

 

Basically, different forms of Carbon usage such as flights, car travel etc are calculated and added to the shopping cart.

 

This looks at first sight to require a bespoke e-commerce solution, but obviously I'd prefer to keep costs down if possible.

 

All helpful suggestions appreciated.