>>2525040>>2525054timmermade, montbell, feathered friends, as some random examples of companies that sell good /out/ puffies. you want either down or 7.5oz apex. any good seller should have a chart or some sort of info on what temp range their down jackets are good for. all 7.5 apex jackets should be fine for the temp range on the synthetic side of things.
do you have an active layer for that weather? you're not gonna be hiking in the puffy its your warm in-active layer for when you're standing around at camp and shit. pick up a grid fleece or an alpha direct hoodie or something too.
you're also gonna want some good thicker wool or synthetic baselayers. synthetic's perfectly fine, go wool if you're gonna hike more in the future its worth the investment.