I think the TOS production phaser rifle, had it ever been made, would have been a butt stock module that plugs onto the Type II phaser. Check out Matt Jefferies' drawing of the phaser seen on this thread at the RPF:
It describes the phaser pistol as "Hand Phaser Unit #2," shows the small hand phaser as "#1" and describes the handle as "Power Pack Unit #3." On the bottom of the tail end is a note saying "Recess to recieve spring lock from Unit #4" which is otherwise undescribed. But it seems to me that the intention was to have a stock plug into the back of the Type II, possibly wrapping around the radiator vanes at the back. I've often wondered what it would look like, possibly a shoulder stock, or possibly an L shaped unit that makes the whole assembly look like the TNG phaser rifles. I've played around with sketching ideas but never came up with anything that didn't look hokey.
--Alex
It describes the phaser pistol as "Hand Phaser Unit #2," shows the small hand phaser as "#1" and describes the handle as "Power Pack Unit #3." On the bottom of the tail end is a note saying "Recess to recieve spring lock from Unit #4" which is otherwise undescribed. But it seems to me that the intention was to have a stock plug into the back of the Type II, possibly wrapping around the radiator vanes at the back. I've often wondered what it would look like, possibly a shoulder stock, or possibly an L shaped unit that makes the whole assembly look like the TNG phaser rifles. I've played around with sketching ideas but never came up with anything that didn't look hokey.
--Alex