>a well driller and ready-mix
You just need a large drill to make the hole. I was suggesting just a 1" diameter not 8". Actually, 6 to 8" diameter at the top foot or so would make a good funnel. If you mix the cement to a consistency of almost water, you could probably pour it down a 0.75" hole.

And the Portland and anhydrous lime you mix yourself in a tub or bucket, real runny, and pour it down the hole. The materials cost a couple bucks. Its not like it would take a full bag. Run the rod up and down in it to get out the air.

You could have been doing something less tiring, like building a drill press on your back bumper.

I'm thinking that you could build this thing out of stuff you already own.

I feel bad for you. That's why I was thinking about what I would do if I were faced with that very often.

You would have gotten the same $700 whether you spent an hour drilling or 6 hours sledging, yes?
I figure you lost $110. If you lose $100 a week, that's $5000 a year, not to mention the aches and pains.

Say, if I built one for you, would you be willing to split the profit and pay me $25 per hole?