Rehabbing an old well

We moved onto a property that has an old well that was disconnected from the house when the municipality brought public water down this far. According to neighbors, the well used to run dry in the summer and the previously owner had to bring in purchased water so when they had the option to hook up to municipal water, they did. We'd like to put a siphon/hand pump on the well, so that we can use our own water for homestead things like gardens and animals. But I'm not having much luck figuring out to do that with an existing (not maintained) well.

The top of the well, well pump, and pressure tank are in a concrete structure sunk into the ground about 3 ft (that's our frost depth, so that makes sense). It must have one had a shingle roof on it, but that has since collapsed into the concrete hole. I cleaned it out this week but forgot to take pictures before we put the current plywood cover back over it. The top of the well casing/whatever type of metal cover is on the well casing is all rusted and there are 2 black plastic pipes coming out.

Will I need to figure put a way to get that rusted cap off? If I want to hook up a hand pump of some kind, I'll need to bridge the gap between the top of the well casing and 3ft to the top of the concrete hole (i.e. ground level) how do I do that? Could I just connect to one of the existing black pipes? I need to know how deep the well is to choose an appropriate pump, how would I do that?

I'll try to get a picture one of these days with the lid off... but we are heading out of town this week so I may not be able to get to it right away.