I gotta second the idea of a cheapo gas powered semi-trash pump or transfer pump.
We Irrigate one of our Blueberry fields doing something similar during droughts, and dry spells.
Trickle irrigation works real well, IF you can keep up, however once you are behind, and net loss is greater than delivery, you are screwed without a backup method to get back even or ahead.
Trees and bushes both show stress late, and need a constant state of availability or will be stressed without it showing untill much later.
Last summer, the Trees and bushes were showing hard stress in July, but were hurting back in May. Ground moisture levels were just too low, too early.
The advantage of the trash pump to fill a large reservoir, that feeds drip lines, is you can maintain a constant state, and if you get behind, simply flood to make up, and then go back to trickle alone. If you wish to skip the expense, in favor of waiting to install a dedicated drip system from the well later, simply flooding 1-2 times a week works nicely. Just gotta keep up with it.
Another option....PTO irrigation pump.
Keep your eyeballs peeled for a used high volume PTO pump like Hale sells.
Some of the older ones,Goreman Rupp etc., can be had for 3-4 bills, parts for rebuilds are still available, and they cannot be killed.
They move water, fast, and LOTS of it.
Good luck to ya!!
