Almost any tubular pasta will do. You can replace the tiny shrimp for normal size shrimp but I suggest that you saute them separately in a little butter and add them at the end.
Be sure to rinse the shrimp in a little cold water to get rid of the brine they come in, and drain them on a bit of paper towel.
The tiny shrimp from ICA or Hemköp aren’t the best, they are already over cooked in the container. I know the price of those are about 41 kronor, the good hand peeled shrimp will cost at least double that, but those are the ones to use.
You need to keep in mind that the shrimp and salmon are already cooked and to cook them any further will only ruin them. Once you add the shrimp you only need to make them warm enough to serve.
I never incorporate the salmon to the dish, by the time you get it to the table it would be solidly cooked and in eatable. Much better to use it on top and it makes the whole dish look beautiful and impressive.