Here's one from someone who has bought every fly tying material known to man over the last 25 years. If there's one thing which I wished I'd bought on the first day of my fly-tying career it's a good quality genetic grizzle cock cape. The buggers cost upwards of £50 but add a few dyes to vary the colours and you'll have hackles to tie most flies. Please pass this on to your father in law!!! He'll thank you in years to come. Good place to get one is here
Lakeland flytying
Hope I've been of some help!
Gerry