We split Christmases between the two sets of grandparents who are both far away. Santa brings their stockings and leaves a note that their gifts are at home under the tree. (We pay the dogsitter a little extra to bring the gifts out for us.) They also get the presents from the grandparents & the rest of that side of the family and a few things from us to open on Christmas morning.
As for making the trip the main present, I don't see a problem with that. I may be wrong, but I don't think an 8-year old yet knows how much things cost, so wrapping a handful of small things as gifts is probably just about as meaningful as expensive things. It's amazing what you can find at the dollar store! If money is really tight, perhaps some other members of your family wouldn't mind if some gifts from them are labeled as being from Santa. Also, if there is anything "extra" on the trip, like a special meal or tour, that could be put in a card from Santa.