Yes, good old car engine oil/ I've used it for years on all my bikes and have been happy. I've recently tried some of the "recommended" lubes, including those suggested here, and they just don't cut it.

You don't even need to carry lube with you. You can find enough to lube a chain in a bottle or can disposed of outside a service station anywhere, and even on the side of the roads.

Personally, I carry oil in an eye dropper bottle. I place one small drop on each roller, and that will do the trick for at least 2000km of dry-weather riding. It saves having to wipe down the chain afterwards.

The only way to extend chain and chainring/cassette life if to clean often. Probably once a week, you should have a routine in place to do this. It's not that difficult with a wide-mouth softdrink bottle and some kerosene or diesel. Bike maintenance is a way to break the monotony when it sets in during bad weather or enforced layovers. Chain joiners can be a godsend for this job, but I don't think I would go on an extended tour without a pair of the KMC joiner tool that keeps my hands for getting grimy and guarantees instant separation.

But, others have found they can get by just by adding oil to the chain regularly without worrying too much about cleaning. Having new components on leaving helps, too, and you just have to hope that when the wear is terminal, as in the chain jumping or chainsuck becoming a permanent feature of your riding, you are close by to somewhere that has the right components for your bike.

I would also carry a small bottle of light bike-specific grease. In the conditions you are likely to encounter, I'd expect the headset and wheel bearings are going to take a beating, and you may need to do some maintenance of them on the way. I certainly would suggest having the highest quality hubs and headset you can afford. Obviously, if you have sealed bearings, this makes things easier, although a spare set of bearings might be useful.

Oh, and your wheels are top-notch in components and build, too, aren't they?