JDM Sti wagon (new shape)...
 

are these available, or were they dropped when production of the classic ended?

I know there was a MY01/02 STi Wagon, however, it's not the same as the classic STi wagons, which were, I believe, very similar to the saloons, whereas the facelift wagon did not have the flared arches, brembos, front suretrac diff, ally wishbones (or something ally with the suspension), and maybe no DCCD, and possibly other stuff the saloon did. In essence, I think all it really shared was the badging and the 280ps engine. Bit of a letdown as a 'real' Sti Wagon would be great. You could possibly brew your own, but I don't think it'd be worth the cost involved.

no sti wagon for the MY03 shape onwards as I'm sure Subaru didn't want to introduce anything that would upset the launch of the saabaru wagon (like better handling and more POWER :D)