For eyepiece positioning .... nothing beats tube ring/clamps , you can loosen off the clamp bolts a tad and rotate the tube to get a more comfy eyepiece position.
Check out Orion Optical UK (
http://www.orionoptics.co.uk/) who do custom tube rings attached to a dovetail and spacers ,all they need are your accurate tube OD measurement and they'll be only too happy to quote , and you can buy direct from them.
Lumicon have nice 50mm and 80mm finderscopes which are straight through or right angled , and they are cheap too, and you can buy direct from them.
This is what I plan on putting on my upgraded newtonian :
http://www.lumicon.com/telescope-acc...Finder+Body&hn= +
http://www.lumicon.com/telescope-acc...racket+80mm&hn= as I already have the 25mm Xhair and a couple of spare 1.25" stardiagonals.
I don't think my old 50mm Lumicon finder will cut it on the newt .... but might be OK as the finderscope for my CG5 camera platform , the old 60mm Tasco achromat (white tube 1960s vintage) which I'm rebirthing as my CG5's guidescope only has a 30mm finderscope which is WAY TOO TINY .....
You can convert straight through finderscopes to right angled finderscopes , just need to shorten the tube to make allowance for the extra pathlength through the star diagonal.