x2 on Columbia river mandrel bends. They have a pretty nice selection of flanges pre cut out for much much cheaper than ebay as well. The backing plate for an hx35 is $16 through them. Fleabay wanted $80 at the least.
The plate that bolts to the back of the turbine housing. It is 5 or 6 bolts. Covers the wastegate area. Bought a blank one for building a small twin setup. Not sure what the technical term is for it.