They are lot smaller. Less than half the size. I've seen odyssey ones(similar) for around $120-$140. Not to sure on braille $$$. Have seen them mentioned lately and been meaning to look into them. In our gen cars you can remove old battery and tray and fab a holder out of flat steel like a cradle that you can then mount to the frame rail with a couple bolts. So not only do you shave the weight but you also then lower that 6-10lbs helping to lower center of gravity a little.
Hatch Nation #9
"2 by 2 Hands of Blue."