It looks like the porter cable 20v batteries are finally going on sale. I found one in my local store for $7.99.it said there was 11 but they could only find 1.there were a few other stores near me that were showing in stock. No shipping unfortunately.
Lowes. Com link
https://m.lowes.com/pd/PORTER-CAB…100032190
Brickseek link
https://brickseek.com/lowes-inven…1000321
Happy hunting and don’t down vote the messenger!