I have a trip planned 4/2-4/9 from Chicago to Paris on a 763 E- that I paid $600 for. I called to see how much it would cost to upgrade to E+ and was quoted a fare of $1400. I'm wondering what my options are to upgrade with cash? With a 31" seat pitch in E- I'd like to get to E+ and may be willing to spring for a business upgrade at the gate. Any ideas on cost and the best way to approach this? I currently have no FF status with United.