As the proprietor of a small business that makes their product as well as all the other jobs that small businesses require, I was pleased to read the pleasant and balanced narrative of the gentleman's experiences.
I presume that Simon is a one man business and so has to do pattern making as well as wax casting, setting , mould making and all the processes that go into making premiere quality propellers, therefore he will have stocks of standard sizes and types that will be delivered quickly, and the special orders and commissions that will take longer to deliver.
The issue of success in such fields is that reputation is built on the work of the individual, and trying to afford, let alone train someone else to be a clone of you is very difficult especially if you get through several feckless people, with all the employment laws etc that makes taking someone on complex and time consuming. Therefore, the individual craftsman plugs on and will have a large backlog.
If you need to contact a company, be nice, be succinct and don't tell them your life story. We all like a natter, but for every second we are talking, it takes a second longer to get to your order! Once we get back to shows, have a natter there in a more relaxed setting.