Ron you can get that insert without the surround.
That one is actually being sold by a member here I believe.
has that insert and I think http://www.nrauto.com
Hope that helps.
Personally I don't think that big star looks good on the 300E or 190E or any benz that wasn't designed from the factory.
I think putting that insert in is just cheeseball. If I were you, I'd paint the insert black, put the chrome strips back in it, and it will look much better than the grey plastic.
So I've told you where to get it and I've told you my opinion on it.
What you decide to do is completely up to you, if you really like it, go for it.