"The ULN2803 octal darlington might be useful for this too."
Not really it has a large voltage drop across its outputs.
If you want them all in parallel, this one would be good
https://www.digikey.com/product-detail/en/infineon-technologies/IRL540NPBF/IRL540NPBF-ND/812000
If you want them more controllable, individually, or small parallel groups then TPIC6A595, TPIC6B595, or TPIC6C595