John that Hall of Fame countryside is a pretty area, been there a bunch of times.
It can be tough trying to figure out the most economical fix for a leaky pond, if you could fix the leak you still could be at the mercy of a dry year, having a well for a water source would be the most reliable fix even if you did get the leak plugged.

As usual it always seems to come down to how much your willing to spend to have your pond, there are some on the forum who use a well to supplement their pond, maybe they will chime in and give you their expertise.
If you need more info on a well try posting questions under the (systems questions) topic.