I'd count it as 150 for a decent breast. So for your sandwich it's probably a little less than that at say 120 cals depending on how filled that bad boy was
Cheers! I just have it in a salad box, but I'd guesstimate it as about a fistful's worth. I ditched the bread after MFP made me realise how many cals are in it!
I think I'll go for 150 - I'd rather overestimate than underestimate.