I think the R262s should be Australian-built. Two common railcar manufacturers in Australia are UGL (United Group Limited) Rail, whose default EMU/DMU manufacturing plant is in Broadmeadow, New South Wales; and Downer Rail, whose default EMU manufacturing plant is in Cardiff, New South Wales. Here are 2 more of my ideas:
Toshiba propulsion system with 2-level SiC-MOSFET–VVVF inverters and permanent magnet synchronous motors, like that of the Tokyo Metro 2000 series (this would be the first propulsion on the New York City Subway supplied by a Japanese company)
Mostly stainless steel construction except for ends and rear bonnets (fibreglass) and doors (aluminium)
