Congrats! May I suggest:
1) he wear Dress Blues; and ...
2) contact your local Marine reserve unit and see if they can do the crossed swords thing (assuming he and his wife are willing).
I am struggling with this question myself. Our Marine son is getting married in May. A lot of her family are Baptists and then there are his friends.....Marines..... and the guys that are not Marines can certainly keep up with the Marines in the are of adult consumption....I think it may be cheaper to go with a flat rate....we shall see.....