Bad cylinder

It turns out that the fouled plug I mentioned last week is oil
fouled... I suspect that the rings have gone... I will borescope the
cylinder for damage and check the seal on the intake valve stem, but I
suspect the worst... It is burning a quart every 1.5 hours, suddenly...

And the story gets complicated... The engine is roughly 1500 smoh...
The cylinders are old reruns... The case/crank is ~ 1958 manufacture
with nearly 6000 hours in the log book... It is unlikely that Lycoming
would take it for core credit... So the options are (in decreasing
cost):

Factory New (How much? I see, umm, let me get back to you on that.)

Factory rebuild - unlikely to get core credit, so total cost about $25k
+ labor

Field overhaul (my mechanic refuses to OH engines anymore so I will
have to ship)
~$9K base cost plus parts that won't make it - I'm guessing $15K +
If I remove the engine I will have the mount overhauled, new hoses,
etc...

TOH with 4 new Titan cylinders - ~$4K plus Shipping and Labor

1 new Titan cylinder - ~$1K plus S&L

Overhaul the cylinder - maybe $500 total...

Overhauling one cylinder gets you into RCR ( russian cylinder
roulette)...
Both the mechanic and I agree this is not the best route, but it is the
cheapest initially... He wants a factory reman to hang, of course...
The issue with changing out one cylinder is if one cylinder is gone at
1500 hours, how long before the next one, etc...

Doing a TOH at 1500 hours doesn't initially seem cost effective, but it
is where I am leaning... The bottoms on 320 150HP engines will, in my
experience, go lots longer than the 2000 hour recommended overhaul...
If I can get another 1000 hours out of the bottom (2500 total), which
is possible, both I and the airplane will likely be retired from flying
for other reasons...

decisions, decisions... daaayum...

denny