The other thing you could try are one of these "high Mileage oils"
Yes, only a temporary solution, but I have had fairly good luck. The premise being that there are conditions in the oil that swell the seals. Does this repair what's broken? No. Does it often reduce temporarily oil consumption? Yes. I have use Valvoline MaxLife with good results.
In my experience, if the cat isn't too saturated and with your low miles, you might be able to clean it out. Fresh plugs, the snake oil and an extended run to get it very hot, might solve the situation short-term.
'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)