Putting on my old curmudgeon hat now, and saying that you can do what we did, back in the day, before there was PE or aftermarket anything, and scratchbuild those details.
And yes, I did build a model in the snow, uphill, both ways!
Seriously, though, you really can scratch a lot of things that folks otherwise represent with PE or resin or whatever. Some of you may know Bob Ciccone from the shows, he builds 1/700 ships, and while he does use contemporary aftermarket materials, he also scratches a lot of his details. He makes rails, for example, from stretched sprue, and it looks fantastic. The judges think so, too, since he wins awards for his models. But this is to illustrate my point, that you can do those things yourself, too. Aftermarket supplies are first and foremost a convenience.