It looks the same in the photos. There is a plethora of info on the use of a 9x50 finder as a guider! Search button is your friend!
On the note of adapters - you wont need to spend £50 but around £28 should get you a nice adapter from Modern Astronomy. If you want to get good guiding I wouldnt scrimp on the connection of the camera to the finder.
I guide my ED80 rig with a finderscope guider, and it seems fine at around 520mm FL. I plan to guide my 1500mm newt with one was well, but just havent had a chance to try it out yet. 1500mm seems to be quoted as the upper limit for the 185mm FL finderscope.
You'll need to change or modify the mounting bracket too, to eliminate flexure.