A good used engine is available locally(S.E.) for ~$400-500 depending on exact vintage and condition. Yours has sat since 2013. Your mechanic should change his work designation, as he apparently does not know which end of a screwdriver to use as a hammer. Being rude, he is apparently incompetent, and cannot read the readily available posts about changing the timing belt on a Lima 2.3.
Search here for directions, or ford-trucks.com, or ranger-forums or fordrangerforum or do a google for images of a Ford 2.3 timing belt. You will likely get thousands of hits.
The process is relatively simple, and does not take a rocket scientist to accomplish.
If you have access to a torque wrench ($15 @ harbor freight) a 24mm(??) socket for the crank pulley bolt, a socket wrench set ($5-ish@harbor freight), a flat-blade screwdriver to loosen the hose clamps, and some time, you can do it yourself. Or not.
I would not give another dime to your 'mechanic', and would actually ask for a refund as he did NOT successfully change the timing belt.
Letting the truck sit is not a good thing to do. Brakes start to leak, rust, etc. The battery will sulfate and become useless, requiring replacement. The bearings in all the accessories will start to dry up, and so on.
So, choices are 1)new-to-you truck, 2)fix the fix of this engine, 3)get a good used engine and 4)get a rebuilt engine. I would not put that many $$s into an truck that old unless I was going to run it for 3-4 years to amortize the cost. Your choice.
tom