Aggie, there will be a seperate back available for standard cut 8x10 holders.
At this time the holders are proprietary to these cameras. By designing from the ground up thicknesses and T dimensions are the same between formats. This greatly simplifies construciton of backs and holders and keeps costs down. that allows me to provide a pair of holders with each camera and then sell additional holders for quite a bit less then current offerings. For example an 11x14 holder would sell for about $150 or less then half the cost of other holders.
I plan to someday make similar holders to fit other cameras. But each format requires different T-dimension and thickness of materials. Those will probably be wood construction. But that would be a ways down the road.
After I get the initial cameras completed I will offer to build backs to fit standard(?) holders. With the non-ansi sizes such as 7x17 or 12x20 I will probably require a holder from the customer to insure the right fit.
As far as deciding to go with the hinged frame or tape, I will probably provide a choice with the non-hinged version slightly lower priced.