Have you seen the EV West conversion kits (here)? They use a single AC50 which seems perfectly adequate in terms of performance.
AC50 (or 51?) is what Jehu uses in his split as well (here).
It might also be worth considering a small Tesla motor/inverter/trans/diff... I know that sounds crazy but I've heard some people are picking them up for peanuts from car breakers who don't know what they've got