t3/t4 50 trim .48 a/r

wheres the best place to order one from for my car..? 

Pagparts.com.  You can choose from 270 or 360 thrust bearings.  Plus i cant find anyone selling a 50trim for less than $625 now.  About 6+ months ago you could get them along with the 57 and 60trim for $575 for the 270 bearings.

You might wanna look into the 57trim. It's cheaper, and can handle the same power at a lower boost. 

But he has a manual.  He can boost far more than you can/will.  The 57trim will surge at about 20-22psi.  SInce you wont run that much, its fine for you.  He can run a 50trim to 30+psi if he wants.

boostfactory or 20 squared is cheaper. 

Bf = $625
20sq = $619 ($6)
 
Like i said, $625 is about as cheap as i have seen them.  BF used to sell them for $575 not to long ago

well pagparts is 785/845 so i thought i'd mention those 2.

LOL, those are T04's.  The t3t4's are $639. 
 
And the only reason i said them is because its the only place i know that lets you choose the 360 thrust bearings.  These oil better and to some people, that extra $50 would be worth it.  Not to mention Arnold is a great asset to the VAG community

From Turbo Mag
 
The 270 vs. 360 Dilemma
Many conventional journal- bearing turbos use a 270-degree thrust-bearing washer (at left), while the new breed of conventional and ball-bearing turbos employ 360-degree thrust bearings. The advantages of a 360-degree bearing include a full circle of lubrication, six orifices on the washer instead of three for the 270-degree unit, and an updated pad strategy to better disperse oil where it's needed. Turbonetics uses 360-degree bearings on all of its T04B and T04E turbochargers. There isn't much of a dilemma here; if you have the opportunity to use a 360-degree bearing, jump at it.

and if i get a tial 38mm, what bar should i be looking for?

Depends on what psi you plan on running.  The higher the psi, the faster it will spool but the lowest you can set it.  Most stick with a 7psi-1bar spring and tune from there.

on pagparts it says 1bar is 14.5 psi http://pagparts.com/perfpts1.asp?pprd=gtwastegate&mfrid=193

7psi - 14.5psi.  Is that a little more clear?  Sorry

cincy, you thing the 034 tube mani is worth the 900 dollar price tag?

Depends.  If you want a fast spooling turbo and worry free driving, i would go with a nice cast manifold.  If you dont mind a tiny bit more lag and much more top end, a tube manifold will make a huge differnce.  Plus if you go with that, you really should go with a .63 housing so you can optimize flow. 
 
Here is a good chart to show the differnce between log and tube.
 
 
GT30R
Compressor 76.2mm, 56 Trim .60 ar
Turbine 60mm, 84 Trim, .82 a/r
AER Stadalone Management (England)
Both Pulls @ 23.5 psi
Superflow Engine Dyno

Full Race
hp - red
tq - teal
ATP
hp - blue
tq - green

 

is that the down pipe setup i should get with the tube mani? Will the car still pass emissions you think, if i get two o2 sensor holes?

If you have a decent cat welded on, you should pass emissions.  Yes they sell the dp for like $250 on the website