you still haven't made clear of you are studio or location based. I suspect the later, because of Deardorff, but might be wrong.
If the latter, there are numerous options for 8x10 folding field type cameras out there - like Toyo (new) Kodak (old) Wisner, Ebony, Canham, etc, etc.
but... you seem to be asking for a digital equivalent to that, and it doesn't really exist if you are doing portraiture.
for 8x10 landscape, a lot of (famous) 8x10 photographers have switched over to stitching backs on digital MF - Cambo or Alpa or whomever.
for portraits stitching is not a good answer, so... you need to use a single shot digital view camera - like the mini sinars, linhofs, etc that are out there.
problem is that you have got to know and love that long lens look on 8x10" and that big screen to compose on, and now you'll be working with a tiny 6x4.5cm screen and much shorter lenses, so you simply wont get the same effect. no way around this really.
to be honest in such situations you can get some imitation of 8x10 imagery but never the same. I'm not talking about sharpness/color quality, you can get that, but... about focus, focal length, work techniques, camera dynamics, etc. In my opinion its best to embrace the new qualities of the camera you can have, rather than trying to make it imitate something it isn't.