Filson. I have a pro deal which makes it far more palatable but their Alaskan Guide flannels are the best I've ever tried, the waxed canvas jacket and the mackinaw wool cruisers are both worth the hype. That mackinaw wool cruiser is comfortable from 50°F to 15°, it just breathes and regulates your temp. I bring mine all over the country on my travels. The Mile Marker is a great Barbour-adjacent coat, nice for southern winters where it's often like 38° and rainy. Completely blocks then wind and acts like a shell so your midlayers can do their job. Plus it looks good and acts like armor going through the bush. I do a bunch of PFAS research so I can't wear standard outdoor/tech gear since everything has a DWR coating and that can cross-contaminate my samples. Gotta dress like a pioneer half the time.
They aren't showing the Mile Marker on Filson website right now, it'll be back when it's back in stock but I have this one and it's a handsome jacket that can dress up or down. With a nice wool sweater underneath you'll be fine in anything Cali winter has.
https://www.ebay.com/itm/1253353227...vwE16EPgT9-cqG2EKJqSBvXMAO11H9i4aArfUEALw_wcB
Don't buy regular stuff like long sleeve or t-shirts from them, you'll be overpaying, but the things they do well like wool and waxed canvas, they do exceptionally well.
Darn Tough for socks. They are simply the best and worth the price.
for boots, I like Tecovas for western styling. Nice handmade leather and can be resoled. Same goes for Becket Simonon (loafers), Clark's and Meermin for Chelsea boots. The waxed kudu leather Chelsea's from Meermin are very cool and look nice, comfortable to walk in. Redwing is another good one for all round.
I like Orvis and LL Bean for business casual office khakis.
Edit: Lol I completely misread the explicitly business casual part. Sorry. Gonna edit this for more that leaning, dropped here in the meantime so you know I'm at least rectifying my illiteracy.