Product price based on excel table virtuemart

I have a jewellery website which sells wedding rings, I have a table with all the weights, widths and finger sizes. I need to have a system similar to a competitors site where the price is calculated based on a few factors mentioned above. The site that I am basing it on is [login to view URL] I am attaching a sample for the table. i want to be able to upload a excel file which can then have a global setting for a per gram price for each metal ie platinum, 18ct white gold and 18 carat yellow gold. The website will need 3 attributes to enable it to calculate a price so the customer must choose if they want a light,medium or heavy weight ring, then they must choose a width ie 2mm, 2.5mm, 3mm, 4mm, 5mm,6mm, 7mm or 8mm then they must choose a finger size this will run from h, i, j, k, l, m, etc once all these have been input they will correspond to a gram weight within the table the gram weight will be a number ie 4.4 (4.4 grams) some rings will not display a weight this is because they are not available in the selection they have choosen. For an example look at the table attached I choose Platinum profile D Medium Weight 3mm width (this is the left column) now I choose my finger size P so the gram weight for this particular ring is 5.9 this 5.9grams must now be multiplied by the gram weight within the global settings ie £90 per gram which would equal £531 then I want to add a discount for the online price so need it to take off a % that can be changed on a daily basis.