Welcome to FT! I seem to be the one typing the bad news in this forum to others, like yourself, who are trying to book height of the season tickets a couple of months before the trip. Many of us traveling to Europe this summer, booked the tickets in the summer/fall of 2013 and thus, have snagged many of the seats.

Rather than just say no it cannot be done, I would suggest you try a couple of things. First, using your home airport and desired locations, check united for award availability. Is there anything close to what you want? Keep in mind, the time for pickiness was several months ago, now you want seats (or you need to move the trip). Then, check with AA. You can use UA miles over and AA miles on the way back by booking one way tickets. By doing this, you will see what the availability is right now, which of course, is not what the availability is going to look like in a couple of months when you actually have the miles. Do not forget to look at nearby airports that you may need to commute to, either in the US or in EU. You can always move around Europe via relatively inexpensive tickets, but you can't typically get to Europe for that same amount of money.

Then, you need to go to the credit card forum and figure out what cards will get you there. Now quickly can you make the spend? IMHO, if you can't get the card and get the spend done quickly, then, I would consider booking one ticket via UA miles and perhaps, buying the match? This is a taboo idea here, but quite frankly, it is probably the least amount of stress and would allow you to concentrate on hotel points, if you needed a place to stay.

If this is not in the budget, I would reconsider the timing of your trip. By postponing it, you would have time to obtain a few more miles, which would free up some cash for activities, other transportation costs, etc. Even if you have the airfare and hotels, there is still quite a bit of expense in jaunt across the pond.

Good Luck!