You need to go to a leatherworker... someone who takes hides and dyes them and finishes them.

It looks like a brown saddle to me, and the other is a honey. There might need to be a bleaching process, and finishing it so the surface is sealed might be another significant issue. Plus, you'd need to think hard about the type of dye to get the depth of colour and avoid streaking (I have a Brooks saddle that has streaks in the dye, so even the pros can make mistakes).