Does anyone have a source for OEM or aftermarket (but quality) blades or
rubber inserts for E-320 2004 cars?

I just bought a complete set of wiper blades for my 2004 E320 wagon.  

I had the car in for service and called the shop and told them to put
some blades in the car (parts only, not installed), and gave them my
credit card.  

Silly me, I didn't ask what price.

When I picked the car up later on that day, I saw the invoice for the
three blades (2 front, one back)  $99!!!

I couldn't believe it.  I went back in and asked if they had made a
mistake, but no they hadn't.  The old MB I had used blades that could be
replaced by Bosch ones, but I paid the couple of bucks more for the OEM
ones because they actually worked better.

This blade set-up on the 2004 E class looks proprietary, and does not
accept any aftermarket rubber that I have ever seen before.

I typically change my blades 4 times a year.  This price will make me
think twice about that habit. $400 a year in wiper blades is kind of
silly.

The blades aren't really all that great in comparison to the "regular
style" ones.  I actually find that the OEM ones that I got on my car new
6 months ago ... streak, chatter, and skip from time to time.

Any advice in another better product or a place that sells them a little
cheaper would be appreciated.

Rich