CAD, even with experience isn't even remotely enough.
You're not designing a switch, you aren't even designing a switch that will last 60mil cycles, you're designing multiple multi part molds can handle millions of cycles of rapidly heating, cooling, and quickly ejecting those hyper precise 60m cycle parts without distorting them. Just the act of injection molding your design means you can't just design how you want, it requires some serious design considerations in order to make it viable, and I don't just mean how many sides it has or axis it needs (those add costs), but how those sides sit determine if it can even be done or how many parts the mold needs to be to make it work.
All this is to say that there's one reason we've had very few entirely new switch designs over the last few decades... Up front costs for tooling and testing.
Even Logitech went to Omron for help designing theirs and considering they're now offering MX switches you could argue even that failed.
There's no cheap way to do it.
It doesn't matter if you need 100 or 10,000 the steps are the same and that's the problem with injection molding, all the cost is up front, you make your mold you pull the trigger and if it's wrong, you'll most likely have to make the mold all over again unless you have a REALLY good machinist and welder on hand who can alter it. We aren't talking a few hundred dollars here either, the injection machine can be rented, the molds are where the money lies and you can spend thousands VERY VERY quickly. With no experience you could easily be into high end Mercedes or even Ferrari territory before you get your first properly working switch, at which point you can crank them out for a few cents each but that first one costs a fortune.
Also, beware China.
While they may give you a better price (assuming your design works), they're just as likely to have them up for sale on Ebay and Ali Express before the boat arrives with your shipment... For the same price you paid or less. Wouldn't be the first time it's happened.
Now if you just want to revise a current design, like raise actuation or meh, contact Gateron and they can set you up (may not even need CAD) but if you want a total new design, bend waaaay over. And no, there's really no one you can just call to help you on this. The people who can do it, are employed and/or own the companies, they aren't going (or simply can't) come help.