wvmarle:
There are hundreds if not thousands of logic level MOSFETs out there.The IRLZ44n is mentioned here a lot. Looks like a good replacement for the IRL540 (at least it has a much lower on resistance). Too bad it still needs >4V on the gate, so still not future proof (more and more sensors and processors are 3.3V).
Thanks. This looks to be good for what I want (5V Arduino) and I can get them for under 1 RMB each.