BACHES Echelle Spectrograph

Please can you indicate which Diamond Steeltrack focuser will fit to an Orion-Optics ODK10 reflector telescope.

I use 1 1/4 eyepieces on a SOlar wedge. For nighttime observing, I use a T2 Zeiss prism diagonal with a 2" nosepiece (which sits in a 2" focuser). I already have a 1 1/4 " polarising filter which fits onto my eyepieces. Can I combine this with a 2" polarising filter, to be put before the prism, and use the combination as a variable polariser for lunar observation (i.e. one polarising filter before the prism and a second one after the prism, and conveniently rotating the eyepiece to get the desired dimming)? This would be very practical, if it works, but will this setup be less good than a dedicated 1 1/4 inch variable polariser?

Does the Solar Continuum filter block or transmit Infra red or UV?

Is it possible to purchase bcf filter suitable for SONY 3N?

I would like to attach the Sky Surfer V to an Orion 180mm Mak-Cass. The spacing between the available finder scope screws is 0.75 inches (approximately 19mm). This spacing appears to be too narrow for the Baader Standard Base that comes with the Sky Surfer V. Is it acceptable to use the center hole plus one of the slots to attach the base to the Mak-Cass or to maybe use only the center hole? If neither approach is acceptable do you have a dovetail mounting base that will work with a 19mm attachment screw spacing?