So I finally bit the bullet and purchased the Sony A7RII and so far, it has been awesome!

Coming from predominantly using a Mamiya 7 for many uses, Unfortunately I still cannot quite get used to the longer skinnier 3:2 format of modern digital cameras..

Realise this is potentially a bit crazy but am thinking of adding a cropped black mask to the LCD and then adding a video viewfinder to the rear LCD...

Something like this...

I know this will add additional weight and clunkiness to the setup but I would really like to keep consistency within my work and this is the only way to do it with the current sensor size of 3:2.. I don't mind having a smaller file size as the 42mp of the Sony leaves plenty of room for cropping..

Does anybody have any experience with using one of these for video (with Sony or other makes of camera) and in particular, does a small lightweight version exist?