I don't think it's available factory built Matt, but Martin's Models will assemble for you for a reasonable price.
There's no drilling and sawing to be done J2s, just filing and swearing - I'm good at both, ex m.navy engineer.....
The parts in general are of good quality, and substantially made to say the least, especially the chassis and cylinders/valve gear. It's going to be quite heavy for what is, as Matt says, a fairly small loco. The 32mm gauge conversion however needs serious engineering input, and is not viable unless you have a well equipped workshop and suitable skills.
The lack of positive wheel quartering is another issue I was a touch disappointed in, squared axle ends would have made life much easier. The boiler is brass too, something I'm not massively keen on.
I hope to get on with her in a few weeks time when things have quietened down some, and I get some 'me time' !! I'll post a few photos then, I think it will make up into a very nice little loco.
NHN