+1 small trim kit
also called Accessory Bag, Fitting Kit, or Fitting Bag. I spoke with a great CSRep at SRAM, she confirmed that the kit is basically all of the small fittings outside of the gears and shell (I.E. nuts/washers/coaster brake clip/ind.chain/etc.)

I'm hubstripping a F&S Dreigang (model 515 w/coaster brake). I needed a few nuts/washers and locating sleeve (attaches the chain to the shift cable)

I ordered the T3 Accessory Bag #00 0599 150 571(compatible with SRAM T3 hub*)
*Most T3 parts will also serve parts on F&S Duo/515/415 models and SACHS H3111 models.

I also needed T3 Shifter kit #00 2215 024 000.

<<<UPDATE>>>
I got my parts from my LBS and yes the SRAM T3 parts fit the Sachs 515. The indicator chain however is slightly different. The T3 indicator chains do fit the 515 hub but the diameter of the end of the chain (thick threaded portion that connects to the cable) is larger.

In short, yes you can use the T3 chain but you will need the T3 locating sleeve (the adapter to connect to the shift cable) The locator sleeve by itself can be hard to come by in the US. It is usually in with the hub.

I made up a PDF cross reference list of part numbers for F&S/SACHS/SRAM. PM me if you want a copy. The PDF has F&S diagrams and some info pulled from the net as well as Sutherland's chapter on IGHs.