Mark, glad to see your going to get back into fly fishing.... I love it... Haven't had as much time for it as-of-late but the weather is breaking and I'll be back out there soon. I hope you do too!
As for the lanyard it's just Para-cord 225 with the guts removed and a needle knot looped around the call....
The plastic snaps I got at JoAnn Fabric's and you just thread the para-cord through them and knot the ends off and snap them together, easy...... Dougie.