Don't try and push it down - make or borrow or rent a fishing tool.
Question is perhaps there is an obstruction in the well that stopped it from going up and will now stop it from going down. quite odd that the pump didnt drop back down the hole
At such a depth a good light lowered at night will show you the program in the hole - maybe just a flashlight from the surface.
A folding hook or rod with small folding fingers that will pass the pump then open would be the item to pull it with. be sure not to lose the whole mess down the hole. There are other tools that the pros can bring out and save you with and that might be the best bet.
Did you feel resistance and were pulling against it when the [hose?] broke. Do you mean black poly pipe?