I ended up with two Nikon MIOJ Variframe finders to match my MIOJ lens collection-
I never bought a vari-focal finder, did not like the peep-hole viewfinder with my very thick glasses. I ended up using a Kodak Retina finder for the 35mm lens, which also has a mask for 80mm. The latter is good for a 35/85 combination. Parallax adjustment is good enough. For the 135- I'll have to post a picture of the Argus finder that I use. The Argus is a bright-line finder, variable mask for 35 to 135, parallax adjusted.
Good enough for this shot with the 'C'ontax Nikkor 135/3.5 on the Nikon S2.
Playground Portrait by
fiftyonepointsix, on Flickr
I modified the this S2 to focus correctly with lenses made for the Contax. Moved the mount out by 0.5mm using some high-quality metal washers and then calibrated the RF using a Zeiss 50mm F1.5 Sonnar. When bought, the S2 was in near-mint condition, but the mount was loose. Someone had CLA'd it and not put the shim back on one of the screws of the mount.
If you plan on using a number of different S-Mount lenses: buy an SP. The parallax-corrected, multi-color framelines for the 50/85/105/135 are a joy to use, the built in finder for the 28 and 35- have fixed parallax marks that are good enough. The prices on the 28/3.5 are way down, I picked one up for $300 in near-mint condition. Worth having.