A total of 3 reviews of this product on Reddit.
I recommend the Team Wolf CIY (Change it Yourself) keyboard for its swappable switches/keys. Goes on sale once in a while. Got mine on Amazon. There’s lots of info about it and quite a few recommend it, just do a quick search. https://www.amazon.com/dp/B01G4PNNCG
I have a Team Wolf Zhuque that you can have for $37 shipped. I modded it to have a removable cable. It is a good entry level mechanical keyboard with hot swappable switches so she can try out different switches. I can even throw in a few extra stitches for free.
I might even have some extra keycaps that I can throw in for like $8.
I don’t know about that site, so it’s hard to say. If you’re looking for that keyboard with black switches you can get it from amazon for $59.99 with free shipping.
It’s hard to find a good keyboard for $50-70. If you don’t mind greens however, you can get a QFR with Cherry MX Greens from Amazon for $66.
The Zhuque is a unique keyboard in that it would allow you to swap switches without needing to solder each key individually. So either way you would be making a good choice.