Here it is - completed! I'll be parcelling it up this week to go to a secret destination in Europe.
The finished size is about 13" by 12" by 3" deep. I decided to try out some of my sewing machine's embroidery stitiches along the edges of the stripes and did free motion stitching on the centre panel. The centre panel was cut 4 1/2" wide and the strips were 2" by 10 1/2". The base was 6" by 16". I sewed the lining into the bag using Kim's method for her charmed gift bag. I haven't got enough of all the fabrics to make another exactly the same but I'm thinking of making a similar one for myself!