I bought loads of stuff from T3 and you're right, shipping and customs were horrendous. The worst bit was that when they sent the first order they forgot to put some of the parts in. I'd paid the duty for those parts because they were on the first invoice. When they sent the second parcel which actually had them in, they didn't mark it correctly with customs so I ended up having to pay the duties on that again too. So for some of the parts I got from them I actually ended up having to pay duties twice!
To be honest, if you can do a drawing of those parts, they're very easy to make. I have the majority of the rear end parts available from T3 and I think I'll still machine my own drop mounts to replace the T3 ones. If you can do a drawing, it wouldn't be too expensive to get the parts you need machined. That's what I'll do when I do my next build.
Don't get me wrong, the T3 stuff is nice. I'm just saying that if you have skills/resources available to you then you can easily make a lot of it and save getting fleeced by customs.