I agree with CNCdude on one point. You can reuse the old pickup tube. It will lose some of it's outside diameter from the original install.
I always use a bit of RTV ultra black and apply it to the outside stem of the pickup. Being care full to not get it into the input of the pump. This is the area of the tube that inserts into the pump.
I disagree on the welding. The pump housing is cast iron and will not weld nicely to the thin steel tube. This can also warp the machined housing from the heat needed.
I have extras of those pickups if needed.
