The Carlton pace bowler bagged 5-43 to help dismiss the hosts for just 171 in Rotterdam.
Scotland then crashed to 34-3 and 66-4 before Munsey and Dylan Budge combined to secure a comfortable victory.
It had looked bleak when Matthew Cross was first to go when he chased a delivery from Vivian Kingma and was caught behind.
Skipper Kyle Coetzer followed just six balls later when he miscued a Paul van Meekeren delivery to be caught by Tobias Visee.
The carnage continued when Kingma struck again to remove Calum MacLeod for a duck.
Munsey and Richie Berrington offered partial repairs until the latter, having struck a boundary off Philippe Boissevain, was bowled by the next delivery from the young leg-spinner.
But the partnership that the Scots desperately needed came when Budge joined Munsey in the middle to blunt the Dutch attack.
Left-hander Munsey, cautious at first, led the way with a superb unbeaten 79 from 100 balls, hitting six fours and two mighty maximums.
Budge also recorded his highest ODI score of 40no as Scotland accelerated towards their target, eventually winning with 47 balls to spare.
Earlier, Evans led the way with two wickets in as many deliveries as Scotland’s bowlers took control.
He first dismissed dangerman Max O’Dowd who edged behind and followed up by having Ben Cooper caught by Dylan Budge.
Scott Edwards and Pieter Seelaar offered resistance with a stand of 40 before the later was trapped in front by Gavin Main.
Evans returned to the attack to claim another two quickfire wickets and rounded off an excellent spell when Edwards, having top-scored with 56 including three boundaries and a six, offered a catch to Mark Watt.
While Evans took the honours, Adrian Neill bowled with genuine menace and conceded just 20 runs from nine overs and taking one wicket while Berrington, Gavin Main and Michael Leask were the other wicket-takers.