Westside Models produced hundreds of 60 class engines, better known as C-16's. Even ones with the old KTM motors that fill up the cab run pretty well. Precision Scale class 48's also come up every so often, don't know how many they made, but they aren't rare. What should a 16 year old do? Save your money, watch e bay, and look for brass dealers with on line catalogs. If you are new to the hobby, building an engine from scratch is harder than you think, even if you can print stuff, you really need a brass frame. It takes time, money, patience and skill. Can you develop the skills? Absolutely, but not overnight. Thats why I'd recommend saving up and buying one when you have the money, and start your hobby from that point. One more thing. Expect push back from your parents when they find out how much you are going to spend on a brass engine. Most of us went through this, our folks thought we lost our minds.
good luck,
brian b