In 1977, IIRC, Laslui Lake's rainbows were averaging about 3 1/2 to 4 pounds. The bull trout ran MUCH heavier. I nailed one on a croc spoon and my 11' shore casting outfit(open face spinning reel), that fed the entire camp - 2 wranglers, cook, 2 guides and 6 hunters one supper and 'trout-salad sandwiches' for lunch the next day. I'd estimate it was a good 15 pounds, might have been over that, maybe not - seems to me it was about 34" long- again long time ago, but some details quite fresh in memory. The cook cut it in half to bake it in the wood stove oven.
So - if you ever get there - take a fly rod. The fish are not picky. Once the rains start mid to late August, they'll hit most anything.
Hutlesklwa Creek is also good fishing.
I just googled it not knowing if I had the spelling correct. This is what I got.

https://theannabrown.wordpress.com/2012/08/04/the-story-of-simon-gunannoot/