It is much more comfortable then the Stormtrooper-costume but you really have a bad sight in the helmet.
Most easy to buy a black overall and sew some imperial logos to the shoulders. You may get the leather-part sewed at a sewer but I used the same one as for my Tie-Pilot. The belt is the same used for a Tie-Pilot or Officer-Costume.
There are many different helmets available like the Altmanns or Don Post Classic Action helmet, that can be found sometimes in Ebay. But you may want to modify the helmet. First of all it needs being polished to get a nice glossy look. Painting is not such a good idea because the material is very flexible. The cutouts of the eyes need to be enhanced. Take a sharp knife and cut them a few milimeters wider (remove the lenses carefully first). Another great optical improvement would be to cut out the holes in the nose/mouth area and glue some black mesh behind (I used some from old cars loudspeekers). Then attach some flexible tubes. Make sure to find very flexible tubes, otherwise you may not be able to move your head very well.
This is rather simple and cheap. You most likely want to get a pair of black military boots. These can also be used for other costumes like Officer, X-Wing-Pilot or Tie-Pilot.
I really had great luck to find a complete armor. But I have also seen some selfmade armors using parts of Stormtrooper-armor and wooden chestboxes.Ich hatte das große Glück diese Teile komplett fertig zu kaufen. Ich habe jedoch schon Kostüme gesehen, bei denen erfolgreich Trooperbrustplatten und Schulterstücke verbaut worden sind. Wer geschickt ist könnte auch den Brustkasten aus Holz nachbauen.
I bought some cheap black gloves and got them enhanced by 20 cm at the underarm-area with black leather. Really a cheap solution.