Batboard

I've heard that the batteries in the DTR radios are the same as for some other products and money can be saved by purchasing the "equivalent" battery instead of the original. It's difficult though to figure out which battery is the "correct" equivalent though.

The Moto part numbers seem to be 53963 for the regular battery, and 53964 for the hi-cap battery. The images I've seen of these batteries show a rounded top rather than rectangular.

The used radios I bought all came with a rectangular (not rounded) battery, part number SNN5706B. It fits and works, and looks like it's a 1050mAh battery.

Pics of the 53964 on the Moto site look very tall indeed, but pics online from any stores seem to show the same battery image for the reg-cap and hi-cap batteries. Stores are probably just using some stock photos. The part # of the battery on the store photos is NNTN4655B. I'm not sure if that really is the hi-cap battery in the image (as I say, it doesn't look tall enough) or if that's the part # for the regular battery or it's some knock-off?

My questions are:
1. What is the NNTNxxxx part number for the Moto 53964 battery if there is one?
2. Will this taller battery fit in the DTR550 and DTR650?

Maybe we can get put a list together of "equivalent" batteries for the DTR radios.

Got a new DTR650 and the battery it came with is part # is NNTN4655B, which is shown online as the "Hi Capacity" Battery.
It is larger than the SNN5706B, so that part # must be right.

These batteries are available online for as low as $7.95, while the ones listed with the original Motorola part number are more like $30 - $50.

Has anyone found a supplier selling for the lower price that is trustworthy? i.e. the Battery is the real deal, new and so on? There are so many places to buy this product at the lower price, it's hard to tell which are legit.