What's your current ICE car? If it's a fairly simple front wheel drive platform you can probably transplant the battery and traction pack from a Nissan Leaf or similar into it.

Incidentally if you can get enough cold water into it you can get around 150bhp out of a first-gen Nissan Leaf motor for a few seconds, which is really all you're going to need.

There's a guy in the south of England who makes tubular steel spaceframe chassis replacements for VW Beetles, that are compatible with most kit car bodies. Instead of taking a hard-to-get Beetle engine and gearbox they take an MGF engine and gearbox, but I bet you could cram your Leaf motors and batteries in. There you go, now you're running around town in a ridiculously quick electric beach buggy. How cool is that?