11 speed bits needed

I'm updating my gravel-ish bike, converting from 9 speed to 1x11 as cheaply as possible, so am looking for the following bits:

• 11 speed bar-end shifter (just r/h, indexed, works with MTB pull ratios - like this Microshift one
  
• 11 speed rear mech which will handle a 11 - 46 range
  
• 11 speed cassette, 11 - 46T, if still in good nick and not heavily worn
  
• GXP bottom bracket suitable for a 1x Rival crankset — am switching over from my current (square-taper) setup.
  
  

grateful for any and all offers! Would need posting as I'm in Newcastle.
thanks.