Batteries are definitely still available. I haven't priced one recently, but if you do a google search for 7.2v Makita batteries, you'll find what you're looking for.
On the other hand, for the price of a couple of batteries for that drill, you're well on your way to a new drill and batteries. Nowadays, with lithium ion battery technology and major advances in the drill motors, you'll find a new drill has a lot more torque and holds a longer charge. They also put lights in the front, which are very cool when you're under a sink in the dark trying to screw something in. It depends, I guess, how much you use it, and what for. Do you want to be able to drive 3" screws into framing lumber without a pilot hole? Maybe not.
There are times when I use my 12v impact driver all day and can't imagine trying to make do with my old 9.6 v drill, but I still keep it at home, for just in case. And makita is still tops in my book.
BTW, here's a link to a downloadable .pdf manual for your tool. Makita 6019DWE
I hope this information allows you to resolve this issue. If you need further assistance, please post back with a comment to this thread.
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