22 Short Rifle MkI?

Have been interested in the 22rf enfield trainers for a number of years. A first query would be about the "22 Short Rifle MkI". In my 90's Skennerton book, he has that 5500 were made yet I have never seen one for sale. On the same page (412) he has 1000 of The MkII made and I have seen a small number for sale here and there; there are two for sale on two sites right now. Does anyone have any different opinions? Thanks, C-

You seem to have all the information you need to make a decision. If in doubt, buy them both.