United SFO-NRT has upgrade availability on the days I want to travel. $1550 + 60,000 miles per person. I have the miles right now and could book this ticket immediately.
I am 9K miles short on enough Alaska miles to buy two Northwest business-class tickets. Unfortunately, NW appears to only give Alaska one business class seat for their PDX-NRT route; there are no dates at all with two seats available. The agent at Alaska was very nice and found this routing that has a pair of seats, and she can get it for us if I can find the other 9K miles within 72 hours: PDX to SEA (Horizon), SEA to HNL to NRT (Northwest World Business Class).
Getting the miles into the Alaska account is the issue. If I transfer them out of Diners Club or my Marriott Rewards account, it will take 3-6 weeks to credit my Alaska account and the seats may vanish. I can buy the miles outright immediately from Alaska for $225. Mind you, I also need Alaska to credit the 569 miles I flew last night -- it's that close -- so I might end up spending $250 to buy 10K miles just to be sure. These "instant miles" would post to my account immediately, so I could use them right now and jump on the roundabout routing.
The roundabout routing is nearly free ($108 in fees and taxes, plus the $225 for the instant miles), but requires leaving PDX at 6:20 AM (thus arriving at around 5 AM), and we'd be traveling for around 21 hours before arriving at Narita around 6:20 PM local time on Tuesday the 28th. I'm sure we'd both be in terrible shape after such a trip. And due to other constraints on our travel, we wouldn't even be able to enjoy a stopover in Hawaii, even if allowed by the fare rules.
The direct flight from SFO would be around ten hours, leaves at 11:30 in the morning and arrives at 2:15 PM (next day). It is vastly more expensive, but we might not be quite as wrecked by the experience.