Sorry I don't know much but the mulled wine is higher than normal wine because of all the extra sugar and other bits they put in, but they usually only give you a small mugful of it.
I went to the german market in Leeds and had a pretzel with camembert and cranberry sauce, after looking online I counted 18.5 for the pretzel 2 HEB on green for the cheese (so would have counted 12 syns) and 3 syns for the sauce. I have no idea on the sausages, they'll be higher then the hot dog sausages in the book, but personally I'd use that as a guide and add some syns.
Maybe what your best doing is planning when your going and saving some syns for the rest of the week and then going and just enjoying yourself