And, to answer the question, measure the current steerer tube in mm, then buy the fork most close to that measurement but always taller (you can't make it grow more!) and then have it cut to proper size. So, if you needed a 140mm fork, buy the 150mm. If you need a 165mm fork, buy the 200, not the 150...
The original fork on that supercourse would have been painted the same color as the bike on the upper 1/2 or so, and then chrome for the remainder down to the tip. Not sure how a new black fork will look with the current color, but thats up to you!