I’m looking to find a submersible pump to place in a stream on my property for the purposes of pumping water to a small irrigation cistern about 300 feet away (and 10 feet higher in elevation). Preferably solar powered. Anyone have any recommendations?

Hi Chris,   Sorry, no advice on a DC pump but have you considered a ram pump? Found a video which seems to somewhat match your situation: Ram pump

Or a platypus pomp which has blades spun by the flowing water which pumps water away from the stream. Rams are beautiful works of engineering.

Here are a couple old standbys and one found on a brief search.

https://www.altestore.com/store/solar-water-pumps/submersible-solar-pumps/shurflo-pumps-accessories/shurflo-9325-submersible-pump-and-902-200-shurflo-controller-kit-p10659/

https://www.altestore.com/store/solar-water-pumps/submersible-solar-pumps/sun-pumps-c688/

https://www.walmart.com/ip/WALFRONT-1-2Inch-12V-Submersible-Deep-Well-Water-DC-Pump-Alternative-Energy-Solar-Powered-Pump-Deep-Well-Pump/678331513?wmlspartner=wlpa&selectedSellerId=15913&adid=22222222228251257679&wl0=&wl1=g&wl2=m&wl3=295084066277&wl4=aud-566049426705:pla-521696578785&wl5=9058203&wl6=&wl7=&wl8=&wl9=pla&wl10=118787315&wl11=online&wl12=678331513&wl13=&veh=sem&gclid=EAIaIQobChMIpYmb8pjG4AIVCQdpCh0YEgMWEAQYCSABEgJ3pvD_BwE

One of the first utility applications i saw was a submersible shurflow pump in a river to purify water by reverse osmosis during a large wilderness event. Just a rope across and a rope down  to the pump from the middle and some odd lot of panels, maybe 200w laid out on the ground. It provided overflowing amounts of pure water throuought the event and for a good many people.