In reply to SuperstarDJ:
If you want a neat and effective repair pay the very reasonable £35 for a skilled professional to do their work. Alpkit essentially made my £300 down jacket look like new after I committed to a very ungracefull belly mantle on gritstone in it.
If you want a cheap repair Decathlon sell black down repair patches. If you want a colour match, then sail tape usually comes in a variety of colours. All sub £10.
if you want a really cheap repair use any old duct tape and replace when needed.
If you want the best of both you can make your own patch to cover the entire damaged baffle. Fairly easy if its not a box baffle down garment.