Sorry to hear about this nasty rash. As I've mentioned several times, each person's reaction to the urushiol induced rash will vary. What works for one won't work for another. I'm in the "ignore it and it will go away" camp - not something that works for most but it does for me. This is an allergic reaction and will vary not only from person to person but also from incident to incident for the same person.
That said, it will run its course. The Academy of Dermatologists recommend going to see a physician if the rash is on the face, on private areas, or covers more than 30% of the body. Otherwise, they recommend home remedies. Have you tried baking soda? I've read many positive comments about this and it is one of the home remedies recommended by the AAD.
Make sure that you have clean everything that came in contact with the oil including under your fingernails. You could be reinfecting yourself. Also one thing to keep in mind is that this is a delayed allergic reaction and so depending on the concentration of the urushiol oil at a particular site and the thickness of the skin, it could be days before a rash occurs (or just hours especially for sensitive areas).
Scratching does feel good though doesn't it? The only problem is that you might cause an infection and make matters worse. At this point things that contain solvents aren't going to help much. What is on your skin has bonded and so now you need to treat the rash. Keep the rash clean and dry. Find a drying agent (like baking soda) that works for you to help clear up the rash. And it will all take its course.