None of the 300D series were sold with standard transmissions in the US. The 240D had an optional 4 speed manual tranmission, but thats the 4 cyl engine. The 190D series also had an optional 5 speed manual transmission.

I have often thought about how much it would cost to import a 300 turbodiesel from Europe with a standard transmission. If I did, I would want a 5 speed, and I'm not sure they were made. The one on ebay can be found at: http://cgi.ebay.com/ebaymotors/aw-cgi/eBayISAPI.dll?ViewItem&item=600916098

I emailed the guy, and this was a 4-speed.

Hope this helps