Mobile hotspot device suggestions

Does anyone have any input on a good mobile hotspot device to use for Photons in the field that aren’t near WiFi? Looking for something with good reliability and inexpensive monthly service. This will be used as a temporary stop-gap until we can get Borons in later this year. According to our account, we’ll use approximately 5Mb total between all devices currently in the field, or less than 0.2Mb per month per device, so not a lot of data going through these devices, this may increase, but some data plans I’ve seen are set up for streaming and home use (understandably given their target market) and are priced at $60+ per month.