Wait a second. I don't mind paperwork.
In this case, Sergeant what's-his-name could look up prices for HDDs on Amazon, fill a form asking for 100 dollars to buy a larger HDD and 50 dollars to pay for installation services and be done with it.
Yeah, let that non-IT guy do the procurement process. I mean, how much worse can it get than what they’ve already done (implementing a critical system to run on a desktop) anyway?