As mentioned above RCI has a section to look for a 7 night stay for less than 10K points but it is rare to find one costing less then 7,500 points. When RCI has a sale on (as they do now, 30% off required points) they don't seem to discount the under 10K points resorts at all. A few years ago I had 4,000 points leftover and could not find anything to use them on. I didnt want to pay RCI's fees to extend them to the next use year so I just let them expire. I am usually pretty good at booking resorts that use up most of our points. This year we had 50 points left.
Booking a shorter stay will not necessarily use less points, they are often more points, plus you need to pay a housekeeping fee on top of the exchange fee.
Diane