Considering that it's a once in a lifetime thing, so far anyways, I would say you could spend a lot. Up to you to determine how much a lot is.
That's the conundrum, currently trying to decide on what my quality of seat/cost tipping point is. Not worth the effort to only spend $40 and sit in the bleeds but also hard to justify, a month and a half before my wedding/honeymoon, spending many hundreds of dollars to sit down low. But, is half way up the second section on the aisle for a buck and a half justifiable? Also knowing I'm probably not going to see the most exciting player on the team.
If only it was two years ago and I didn't care about anybody else when it came to financial decisions, no stupid "next house" to be looking for, it would be a lot easier to be stupid in this scenario.