Actually, they raised the price for One Time Use Points twice within the last year or so.
They will sell you up to 24 points per year, all at once or in partial groups, for $19 per point.
The trouble is, you can only use them in the 7 month window, and you have to contact Member Services by telephone (or maybe Chat on the website?) to buy them.
I believe you can also only buy them if you are making a reservation to put them on. Though I'm not sure of that.
Maybe you can pre-purchase them, but you still have to call up Member Services to use them, because, like Transferred Points, they don't show up in your online total of available points.
If you do buy them, and you make a reservation and then cancel the reservation, you still get to keep the points, to use on something else.
I'm not sure when they expire, whether in 1 year, or at the end of your Use Year. I suspect it follows the Use Year.