Hey Yoss. As far as the symbol goes: yes - same shape as the first run of Marathon shirts.
As far as the size: that's up to you. I'd be selling sizes medium - through XL (and XXL if its really necessary). As far as the hoodies go, sizes Medium through Large (again, XL size if really necessary - most hoodies are baggy by design anyhow).
So: Black shirt fabric, with a Red symbol is what I'm aiming for currently. I can't do (in response to •M's post) silver - only actual colors. I found that some silkscreening ink only works well with some colors. Yellow, for example - when put on Hoodie fabric turned puce-brown. That's why I didn't offer hoodies in the 2nd S'pht logon run.
I have a feeling Durandal-green would look the same way.
Red, even if it turned darker upon application to some fabric types, would still look good.
I'm still looking into bulk shirt distributors. Post any other questions in this thread if you please...
Regards,
-Blayne