Just out of interest why wouldn't you just buy the one from Gardiner?All you need to do is looks at the Gardiner website listed pump and play snap with Amazon
You know your battery is 12v so therefore you need a 12v pump
Looking at the Gardiner pump you'll notice it's a small bore push on hose style
https://www.amazon.co.uk/ETXP-Diaphragm-Pressure-Automatic-Watering/dp/B091C2BNPB/ref=mp_s_a_1_18?dchild=1&keywords=12v+100psi+water+pump&qid=1620047431&sr=8-18