Amazon Prime includes streams of several HBO series, including The Wire...I don't know when the switch was made to HD: http://www.amazon.com/gp/product/B003AY9U4K/ref=dv_dp_ep1

Note: I'm viewing it from a U.S.-based account/computer...which may be a factor.

edit: I'm wrong. I'm conflating the apparently older 16:9 release with this new one. See [leeshro's comment](https://news.ycombinator.com/item?id=8803190)