The only segment you could upgrade with your fare class is the one from SFO-HNL. Since your companion doesn't have enough 500 milers, you would have to use miles - it will cost 15,000 miles for each of you. I suggest you call the UA 1P line as soon as possible to enquire about miles upgrade availability. The number is on the back of your 1P card. If the seats are available, they can confirm miles upgrades immediately.

You could purchase one set of 500 milers and have enough, but they wouldn't be confirmed right away. You would have to go on the wait list and hope seats would still be available when your turn comes. SFO-HNL is a very popular route and 500 miler upgrades are probably not a good bet.

JR