Well, if all you want is something a little different then you may want to try these. This is sort of a poor man's Hoerner tips that I've seen used and used myself over the years. They are dirt simple and may just fit the bill for what you are trying to do here.

Take a block of square balsa that is as deep as your tip airfoil and slice it at 45 degrees. Keep it square until the angle is shaped so they don't end up out of kilter (there's those tech terms again... ) Now glue, or in your case, mark and drill the holes to fit your wingtips. Now shape the blocks so they blend flush with the airfoil top and bottom. Tape over the finish on the wing so it doesn't get marked during the shaping and sanding. Now glue on the swoopy looking tip plates and match them up to the blocks. This will give you some 45 degree tips that either tilt up or down.

So, which way? Down will hold the air in under the tips better during landings but have an adverse dihedral effect. The upturned tips will provide a bit of diherdral rolling action that may sharpen up a snap roll. But either one should have a little less disturbance to the tip flow thanks to only being on the one side and the more open angle that the plate meets the rest of the airfoil.

And they look pretty darn good too.....