Multiple Options with 2 other fields attached to it

[Vivian Escalante]

Hello, 

So I have a very unique request. Basically, I need to do this: 

Option 1 -> If selected user enters a number for example "2" -> Beside the quantity there's going to be a calculated field that calculates the price for 2 Option 1's 

Option 2

Option 3 

Option 4

I can have a single select dropdown and then a cascading field for each option, but there are around 20 options, so I don't want to do that. Any other more efficient way anyone can think of? Thanks!