2000 RX 300 engine dead. Replace or sell value as mechanics special?

I have a 2000 RX300 w 217K miles. the body and interior are in very good
condition.  NO damage on metal (but minor bumper damage).  The engine runs
badly, mechanic says it's not worth fixing ~ one cylinders is messed up + oil
pump. The engine needs to be replaced.

I just got the front end done a few months before, new tires and replaced with
new headlights (Looks new again).  The alternator and starter are under 2 years
old.  AC works great.  Transmission, no issues. (buttons for front windows and
motor for antenna were the big issues)
I'm on a tight budget right now...

I love the RX300 look, how it handles.  I've tried some used cars and most things
seem a downgrade.  So either I buy a used car for about $3000~4500 or

I buy a used engine (ebay - most likely) for $1000 + $500 for ignition coils, spark
plugs and timing chain. (Get those done while it's easy).  $100 for oil and Misc.
parts.  And maybe pay a local guy (not a shop) $800 to put it in.
About $2400.    I'll have a used engine... and hope it runs well.

Or I sell my RX300 as a Mechanics special?  What would be the value?
I've seen RX300s at Auctions or online for about $2500~3000 that LOOK worse
than mine... with body damage.  In good condition, they are $5000~6000.

What is the value of my RX300 as is?  I can put it here for sale.  (Texas)

Or try my luck having someone put another engine in it?