Try to pick a pasta dish, tomato based if possible. I did create a thread on here that gave ideas of what kinds of foods to pick if you're going out... I'll see if I can find it again!
If you want to stay within the syn area, arrabbiata is a good one usually, and bolognese, but your carbonara's and Lasagnes are likely to have much higher Syns.
The main thing is that you enjoy yourself!
and don't be too worried if you do find you go over on your Syns, as long as you straight back on plan the day after, it won't be that bad