All the miners listed below are compatible with the Helium network, the only significant roadblock this project is facing is that they cannot keep up production of hardware fast enough to supply the demand for miners, that being said when you order your miner expect a wait time. I personally use the RAK Hotspot and have found that it works very well with an upgraded antenna.
Nebra Hotspot https://nebra.io/hntin
Bobcat Miner https://bobcatminer.com/
RAK Hotspot Miner https://www.calchipconnect.com/products/rak-hotspot-miner
SyncroB.it HNT Gateway https://syncrob.it/