Astronomik OWB CCD
(EOS Clip) Type 2
The OWB filter would usually not be designated as an "astronomical" filter. The intention is to enable converted DSLR cameras (modded to remove the inbuilt IR-filter) to be used for 'terrestrial' photography.
This is new and unused (not suitable for 60Da cameras)
Bintel $ 189 + post :
http://tinyurl.com/aqmnaee
Asking $100 post free.