Declining the trip could be a career-limiting move. I would tread carefully.
Is this about not wanting to give up a weekend day? If so, then the compensation part doesn't matter, weekend time is personal time, end of story. Perhaps next time the meeting could be on a Tuesday so you could travel Monday.
Is this about not wanting to "work" without being paid for it? This is harder to argue (people worry about looking selfish) but easy for the boss to fix, since by either paying you or offering you an extra day of vacation time, the boss can get you to go to the meeting. (This is why it's important to know your objection.)
Is this about not wanting to waste the company's money on plane tickets, hotel rooms, and your time, when someone could cover for you? That is so not your problem. If you're willing to go, go, and leave your boss' job to your boss. I have flown literally around the world to deliver a single one-hour talk, and have a few days of networking and socializing. Everyone involved thought that a good use of time and money.
Is this about finding such a long flight, and presumably a time change, and having to sleep in a hotel and eat in restaurants, unpleasant? If it is, even a mid-week meeting would never work for you. You need to make that clear.
Once you know what your sticking point is, don't go and say "I want to teleconference to that meeting." You will be forcing your boss to "interview" the problem out of you. Instead say once of these.
- I don't want to (or can't) give up my Sunday to travel to that meeting. I can teleconference in, or X can take my place if that's ok. In the future if these meetings are midweek I can go to them.
- I am not willing to give up my Sunday uncompensated to travel to that meeting. I can teleconference in, or X can take my place if that's ok, or can you give me an extra day off this summer as compensation?
- I am not willing to travel that far for business, ever. I can teleconference in, or X can take my place if that's ok.
In all three cases you may find your boss demands you go and tells you your job is on the line. It would be good if you knew in advance how strongly you feel about this. Will you quit over it?
I also encourage you to take strong look at the bigger picture. There are 10 hours of meetings, there is probably an evening event, there is a chance to meet and socialize with a customer or regulator or colleagues from another location. You could get tremendous value form this if you knew what to look for and what to gain. Your boss can help explain this to you, if you ask correctly. I dont just mean a nice dinner and a chance to take a picture of some tourist attraction far from home, I mean an understanding of the dynamics of your business, your firm's relationship with whoever this meeting involves, how contracts get assigned, and so on. Approached as a learning opportunity, you might see this as worth the effort, whereas just focusing on "your" 3 hours doesn't feel that way.