Robinson R22 is < $300k.
Furthermore here are some service-life-hours comparisons between components on an R22 and an Enstrom F-28C of the same category ( edit: updated from the FAA TCDS ):
Main rotor blades: 2,200 / unlimited on-condition
Main rotor spindle: 4,400 / 17,700
Tail rotor blade: 2,200 / 3,100
Tail rotor attachment: 2,200 / 6,200
Incidentally Mr Robinson originally designed the R22 with a target list-price of $22,000, hence the name.
Most of what I have seen comes from the Instagram feed of Bradley Friesen who seems to have some pretty awesome pictures of where he's able to land his R44. Makes me want to move to BC.
I expect that to be on the low side, given it is information from the manufacturer, and given that I spotted one white lie: they get at the $140 by assuming 8 gallons per hour, then derive $0.90 per mile from that, but casually mention a speed that uses 9.5 gallons per hour at cruise speed. A tiny difference on that $/mile figure, but it would add about $8 to the 'dollar per hour' number.