Turbo for 855 Cummins

My turbo went out and started passing oil out exhaust side, I started looking around and found 2 turbos in good condition without shaft play for 75$ each. That’s very cheap so I bought both, but they are a little different from each other. Which would be better for a 1971 350 small cam. VT or AR and will both work. The intake side looks different

 

Top 2 are the AR-12606 bottom 3 VT-50 I believe

 

The AR turbo compressor housing looks short not much room for the boot, am I missing a piece it has screw holes in it

 

Just wanted to get everything else lined out and make sure everything is up to par before buying a new turbo. After I know the truck will be dependable I plan on getting a new ht3b. But so far so good

 

I’ve tried Cummins but besides build date they are useless he said it is to old and could not find the cpl

 

My original turbo had a rust hole on it and was leaking exhaust and also started passing oil