I’d suggest you check out Boutique Jourdain in Quebec City. We were in Quebec a couple of weeks ago, our first trip out of Ontario since January 2020, and I tried on a Saint James sweater, the Brehat III. It seems like a very good quality merino knit, not too thick but substantial. I should have bought it then and there but didn’t, and now after much hemming and hawing, and thinking that I should be able to get something locally, I’ve finally just ordered it online.
Merino is hard to find, and when you do it can be so thin you could spit through it (as my dear MIL would say). I do have an older one from Uniqlo and the quality is quite good, but the crew neck is way too high so I rarely wear it.