Kinda depends on how you value your time and how many you want to do. You'll sell more if they are inexpensive but you'll work you ass off to fill demand. It will go faster the next couple you do and if you make fixtures etc.... If you bought a cheapish CNC router you could rough them out pretty quick.
Very nice work by the way. I figure my time is worth $50 an hour for machine work. You're a craftsman doing stuff others can't so your skills are valuable, even if you're doing it for fun. If a set took three to four hours, I'd want to charge at least $150-200

I have a side hustle where I repair aluminum oil pans for certain BMW's and charge $125-150 and it takes me about two and a half hours to do start to finish and is mostly labor making and fitting parts. But, a new part from BMW is $400+ and it will fail at some point where as mine won't. I kept pretty busy over the winter but I'd say I have less than a 50% success rate on inquiries. Some folks just don't think it is worth it because of the cost. If I charged $50 I'd never have any free time. I do it for fun, earn a little extra scratch, and help others in the hobby keep their cars on the road.