I'm 48 and have been hunting since 12 myself (sub par clothes for way too many years and also battle Rheumatoid arthritis) and understand your concerns about cold and saving a buck. A few years ago I started to buy high end clothes for ice fishing and it really made a difference in staying warm and comfortable. This year I've begun to purchase the high end merino base layers for hunting - Out of this world expensive, but I "hunt" for sales on the various archery sites and eBay. I think I've acquired most of it for 45-50% off plus a few extras.. Now, for base layers I'm not picky on matching or colors. I don't need to stay warm - I have to stay warm.
Good Luck.