Yes, taking off the outer pocket is easy.
However, adding inside breast pockets can't be done (cleanly) on something that doesn't have a lining. Alltomorrows has a good idea at least for the left side, but your hanging pocket would have to be shorter than the overall size of the outer breast pocket, or else you'll see it. And you absolutely would have to take that pocket off and then re-attach it - and it wouldn't be able to be wider than that breast pocket, either, because you would stitch across the ends of the zipper when reattaching the outer pocket.
But on the right side, there's just no way to do an "inside" pocket when there isn't an inside. Inside breast pockets on blazers and coats are sewn in the lining, and only to the lining, so that they are entirely invisible from the outside.
Founder and Vice-President, Madison Area Costuming Society, a chapter of the International Costumer's Guild
Strange Land Costuming - www.strangelandcostumes.com
Director, SF&F Masquerade
- COSTUMECON34 - Madison, Wisconsin - May 6-9, 2016 - www.costumecon34.com