Really...a fishing boat with a jet drive, bad idea. Hard to manuveur and go in reverse usually. Jet drives are great for getting into shallow water, and are very efficient since there is no drag from running gear, but also require some different hull designs to get proper flow to the impeller to take advantage of the engines power, a poor design can cause turbulence forward of the pick up to get into the engine and quickly eat up impellers as well as reduce efficiency. If your looking at just cruising the boat and do not have a tight dock, it would work, otherwise would be more of a pain then its worth to own and operate.
Sort of sounds like it was removed because there were issues or the owner realized it was a horrible idea, seems like rebuilding the transom and going with an outboard would be best, or rebuild the transom and go with an I/O.
