Most of the pigs on Vermont's Craigs List have some Tamworth in them. The problem is the driving distance can be prohibitive at times! I found the perfect one a few weeks ago but it turned out to be a three hour drive.
I'm picking up an uncut piglet tomorrow to eventually breed my Ms Piggy.
http://burlington.craigslist.org/grd/4653703618.html
Winter pigs are generally a little cheaper but they did look happy & calm.