There are a number of websites online like Joovv and RedLightMan, however Amazon has a wide selection of Red Light Therapy units. I recommend a high power 600 watt unit to reduce exposure time.

See my article on dosage
https://medium.com/@john.iovine/red-light-therapy-power-density-exposure-time-and-dosage-bff1c94fa9e7

https://www.amazon.com/600-WATT-Light-Therapy-Device/dp/B083G5J7PF/ref=sr_1_26?dchild=1&keywords=Red+light+therapy+600+watts&qid=1588543986&sr=8-26