I believe in newer Picos I've been using a PMEG3005AEA - but then there is a protection fuse as well.
I'd say in an ideal world try and get a more powerful diode AND a 500mA polyfuse in there if you really want to be safe, but I guess maybe a smaller diode that will sacrifice itself is best if there is no fuse :)
@Gordon, thanks for the response. I guess a S4 was in place that could handle 1A. I was surprised the Diode gave way and the trace(s) survived... I figured what happened: I created a complete shortcut of 5V to GND with the jumper on the ULN2003 driver board... I did see nothing but noticed the funny smell of a cocked plastic case...
...ooops, blue the SMT diode from a Kickstarter Pico (sticker # 1409).
@Gordon, what is the spec of it for replacement?
Temporarily, I put a 1N4148 in. It runs average 150mA, can run 300mA continuous. Was afraid to put an 1N4007 or a-like in which can handle 1A.