Black Dress Pants and Shoes for a Wedding

Hello. I will be a groomsman in a wedding and need advice for picking appropriate pants and shoes. The groom has selected the following: white shirt, black pants, black shoes, green suspenders, green tie, and no jacket. My questions: 1. I have a SS of these pants from Spier and Mackay. Do you find "contemporary fit" gives enough room in the thighs? I heard that they tend to run slim. 2. Any other recommendation for nice dress pants? (Budget $150 and under) 3. For shoes, I was thinking of just searching on ebay for used or never worn Allen Edmond Park Ave in Black (since I know my size in AE shoes). Any other recommendations? I really just don't think I would wear these shoes much, outside of funerals. (Budget $250 and under)