Just about any decent battery is going to have screw in terminals, meaning terminals don't matter, get the kind for the application.
It sounds like you're looking for a drop in solution when there's not one that is an exact match. More power same dimensions? That's moving from one technology of battery to another and in those cases they're not really concerned with dimensions from one to another as they aren't intended to be a drop in swap.
Likely what you'll find is you'll need to fabricate some sort of spacer or fastener system to hold a lithium ion battery in place. And if you find one that's at comparable size it's probably going to run you $300+
They posted the stock battery info on there which is a banner 53030
That's 30 amp hours
Dims
L: 187mm
W: 128mm
H: 165mm
With that information and the links from the other thread I imagine you could find something close enough that it wouldn't take much fabbing to get it to stay in place.
Do some googling and let us know what you find out. In fact the MARELLI 53034 seems to come fairly close in dimensions and it was one of the ones linked to from that other page.
