I really like the block finish method of dying , as YinTx said it is not easy to do right. I have only tried a couple of times and not nearly as well as your project.
No need to be intimidated, your work is great. You can see the love and craftsmanship put into it. That will be with him for many years. Thanks for sharing.
One source that sometimes is over looked is the Stecksstore, it's worth a look. I have not purchased leather there , but I have hardware and it was good quality and fast shipping.