I had the job done on my 260E (314,000Km or 195,000mi) 2 weeks ago.
it burned 1qt per 500/600mi, without any visible smoke.
Complete valve job, guides, replaced 3 valves (valve stems worn), Replaced camshaft (3 lobes badly worn), 3 valve rockers, timing chain, tensionner, cap, rotor, spark plugs, wires, thermostat, gaskets/seals sets, air filter, oil change"
Total cost: $Can2,800 or $US 1,800. (parts and labour)
It really changed the way the car drives. Looks like I gained back 25/30HP. Runs smooth as a Benz now.
At 1 qt. per 1000mi, your oil consumption is still quite acceptable. I.d wait until something more serious develops, if youy can live with the small leak.