I bought some $30 kids’ skis at my local sports-exchange shop and added some fish-scales to make a waxless base for my 7 year old’s skis to tour with (although he just likes jibbin’ at this point).
I used a rotary (dremel type) tool with a 19mm cylindrical stone. You really don’t have to go too deep and come in at a very shallow angle.
They seem to work well. They’re grippy enough (I could have packed the divets a little tighter) but quiet with good glide in soft snow.