Three little hints...in B.C. you can get free highway/campground maps at the official Tourism Info centres. For their purposes the province is broken up into 6 regions. Detailed campsite info included. As a sidebar I believe that if your trailer is 18 feet o/a length or less then you can use a tent campsite. no power/city water/sewer but usually there's a flush toilet and sinks.. Bigger campsites have showers.
If you need a map overview the province does sell ($3.95) a province wide map with campground locations.
Hint #2 The official Provincial Tourism centres have good wifi.(sometimes after hours!)
Hint #3 In the Yukon we used the old roadside gravel pits for a
boondocking. We always park in the middle of the pits. Gives you a 360 degree view of what's wandering around. This is wilderness.There are no garbage cans so you know the drill.