Batteries have been going in and out of stock quickly recently. Many people have been buying batteries at these places. In addition to those, you might find some authorized DJI dealers who have batteries in stock.
Props are easier to find. You can get them here on Amazon.
Ordered some batteries and props from here last Thursday. Showed the batteries as backordered on my invoice. Got a package today with batteries and props! Cancelled my 9/27 backordered items with B&H immediately.
Ebay is your best bet for Actual shipping, because stock is so limited. I have seen people with early october battery orders no shipping and people who order in december got theres already. No type of first come first serve just like the mavic.
I ordered a batt from Apple a couple days ago, and the status recently switch to "preparing to ship". From prior Apple experience, I'm guessing that means it'l be here in 3-5 days. Also my local Apple store has been getting them occasionally.
Got my 4th battery from NewEgg today, shipped via DJI in LA, I was all in a lather because the FedEx delivery manager said it was 11lbs and 14X10X10", thought they had shipped me a Fly More kit by mistake, I would have held it hostage for another battery