Rubie'sOfficial Disney Star Wars Han Solo Men's Deluxe Costume, Adult Fancy Dress

I am 5'7 at 135 lbs. What size would I wear?

Are the pants separate from the shirt? And would the standard pants fit me i wear a size 34 in mens.

Are the vest and the shirt two separate pieces sewn together or are they the same piece of fabric? Could I separate them if I wanted to do so?

What does Standard size mean ? What size is standard ?