First thing, get someone, (probably Mikelson's from El Campo your best bet) to run a camera down the hole to see what the casing/screen looks like.  Then they can coach you on what your options are.

Some wells in your area (close to the Colorado) are in some really good yielding formations.  Others not that far away, are expensive to pump.  Mikelsons should be able to get the log of the well and tell a lot from that.

As to power, right now electricity is cheaper than diesel but it has some hidden costs such as the dreaded 'demand charge', turn on, turn off for winter etc.  Also to slow the pump you're gonna need a VFD, it will also help with surge on start up and probably the demand charge.  If you have natural gas available, that is an option, as is natural gas ingestion into a diesel engine.