Peristaltic In-Line Adaptor. This eliminates having to use a 50 gallon drum. You can pull directly from your solution bucket and connect to water source. Self mixes solution and water. 

You still need to buy the pump and pressure gauge separate. See link below for Pump and Pressure Gauge. 

https://www.amazon.com/gp/product/B09KRP389Y/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

https://www.amazon.com/gp/product/B08QCWRCGG/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1