Paul,
Those are some nice choices, the Games Workshop stuff is really well detailed. On the other hand they are expensive. Personally I'll second Reaper as having just as good detail as well as being a great deal cheaper.
They have a search engine on their website and I got 161 hits on a search for 'dragon' - many of them are dragonmen or other dragonlike monsters but still there's a good amount of dragons there too.
For example: Stormwing - $60 bucks but he's solid pewter and 9.5 inches tall with a wingspan of 14 inches.
Or Diabolus also $60 with a length and wingspan of a foot.
They do have a number of smaller cheaper dragons as well.
Ironwindmetals also has a line of pewter dragons but their stuff is over twenty years old and not anywhere near as detailed but they are a great deal cheaper though for the size I don't think they're as great a value as the Reaper products.