I use an Artograph 1520 with a metal hood. It's a downdraft model, meaning that the air is drawn through the bottom of the hood. It's also got a charcoal filter on it so that exhausting outside isn't entirely necessary, though still recommended.
The bottom part was purchased from Bear Air for ~$200 (MSRP at the time was ~$280). Note that in this configuration, only a cardboard hood is included. I bought the metal hood from Madison Art for ~$65 if I remember right. However, this was about 18 months ago, and I'm sure the prices for both have gone up since then.
The 1520 is also sold under slightly different names by Micro Mark (~$400?) and Testors (Testors 1520, MSRP ~$500). In my case, it was cheaper to buy the two pieces separately, but you may find different.
As far as I know, if the ventilation on your hood is adequate, then a respirator isn't necessary.