Goodwill is where I have found mine.

www.sierratradingpost.com

I'm going to have to start checking the thrift stores for a wool sweater as well. I'd been hoping a rich aunt would adopt me and buy me a Filson Guide Sweater for my birthday. But apparently I either don't have a rich aunt, or  if I do, she doesn't like me. So I guess it's Plan B.   :D

I found a 100% wool sweater at the army navy store yesterday. Cost 18.00. I was pleased!  I will stay on the bunt though.

Type in military wool sweater over at the auction site, plenty of them. I bought one for 18 bucks when I was green and didn't realize there were bargains that come and go over there. My next cost 99 cents.

If you decide on a 5 button US army sweater Mike, you will wear a large.

Sportsman's Guide and Goodwill is were I find my stuff! If you have young men in your family that hunt DO NOT tell them how great your wool stuff is. Because it WILL disappear come hunting season!
GLENN

Good will stored are the best place for light weight dress sweaters that are the nice fancy 100% merino wool, casmere, angora, alpaca etc.  Not good as a stand alone garment but a fantastic layer and usually so soft you can wear them like underwear right against your skin.  I get them for about $7 on average around here.

For a heavy sweater at the best price, mil surp catalogs are about your best bet.  I like "Sportsman's Guide" about the best just for variety.  If you want a ridiculously thick, warm heavy sweater, click on this link and go to the bottom of the page.  Click the "Austrian Heavyweight wool sweater" for $29.97  I bought one and was absolutely amazed at how thick it is.  I thought the real expensive ones at cabellas were thick but this one has those beat all to heck and back.

http://shop.sportsmansguide.com/net/browse/military-surplus-sweaters.aspx?d=122&c=2&s=306

One word of caution, I don't know if you are a big guy or not but I'm 6' 2" and about 275#.  I usually wear a 2XL tall but can often get by with an XL.  I think the one I ordered was the XL but when I got it and put it on, it was so tight I almost needed help getting it back off.  Bummer for sure as it was a great sweater.  I put it aside for the kids some day.  There are other good ones there too.  The British military one at top right for $19.97 looks just like the USMC standard issue "woolly pulley" sweater I got when I was in.

If you keep checking Sportsman's Guide and looking at the Military surplus section, you'll find some good deals sooner or later.

http://www.ibexwear.com

If near a military base the thrift stores there will have whatever the branch of services wolly pully, usually real cheap,10 to 20 bucks.(got 4...2green,1 black,1 navy blue). I also picked up a nice thin Italian merino wool pullover for $4 at goodwill(like a filson long underwear top), and another Italian heavy merino/alpaca sweater in a random gray/black/blue/red patern (designer camo)for $10. Really cant see spending a C note on a sweater.

I just bought two commando sweaters at sportsmanguide for like $18 bucks a piece, and picked up two wool dress pants and a woolrich zip up coat for a total of $12

One other thing about military sweaters, they make them in acrylic now so be sure it says wool before you buy one.

yeah I made sure they were wool