I like these headphones, but the black foam covers are falling apart. 
In searching for a replacement, the closest I have found is from Sony
(http://servicesales.sel.sony.com/web/viewItemDetail.do?operation=getItemDetail&itemID=533943&category=6&categoryName=Headphone),
and I'm not even sure it's the right thing.  Description says "ear pad
- one only" and they want $14.95 each, so I would need 2!  Seems
totally outrageous for flimsy piece of foam that should really cost
less than 50 cents.

The phone/earpieces are about 2 3/4 " x 2 1/4 ", so the small covers
commonly available don't fit.

Sony uses a lot of specialized parts that are only available at a Sony
Store. Supposedly, that is part of the reason that they are struggling
right now. I don't think you can buy them from anyone other than Sony.

I bought some headphone covers, but they were way too small.  I think
that a generic cover would work if it was around 2 1/2 inches across
and round, because the foam is inherently stretchy.  The main
difficulty is finding covers that are large enough.

I too have the same problem.  I just ordered a set of new pads from
eBay which were only 7.95 for the pair (they are GM replacement
parts).  I should have them in a few days and I will let you know how
they fit.

Regards.