Kenda is closing out their "El Capo" mountain bike tires for $10. You need to buy $50 for free ship otherwise its close to $19 FedEx. It says they are normally $39.95
Sizes available are:
29" x 2.60/2.40
27.5 X 2.80/2.60/2.40
There are a handful of others on sale for $19.95
https://shop.kendatire.