Hasbro Pulse is once again taking preorders for The Vintage Collection 3.75-Inch Jabba's Tatooine Skiff Vehicle as of this post. Expected ship date is 9/1. When these first went up for preorder the expected ship date was 10/4, so looks like it got moved up about a month.
Also Steve Evans has stated via his instagram (look through post comments)
"to be Clear the skiff will be available at regular retail. It’s a pre-sell of a few early produced skiffs. Not a totally limited run like the barge"
So if you miss out on the preorders at Hasbro Pulse, you will find it at normal retail as well.