I’ve seen Griffin and Howe guns with factory .22 Hornet barrels that were struck through and remarked as .22 R2 Lovell.  Not sure if they had to set back the barrel to get the chamber to clean up, or just run the reamer in.  If you had a chamber drawing for the R2 Lovell, you could compare to the .22 Hornet and get a good idea.

The problem with the R2 is the parent case is the 25-20ss which is much harder to find and thus more costly. Griffin and Howe sold brass many years ago for the R2, but it too is difficult to find and wise to anneal the necks prior to use, and keeping the pressure down to maximize life of the brass. If you can live with all of the above, go for it, but a K Hornet or Mashburn Bee and others might be worth considering with the cost and effort saving. Just from my experience with the above.

It sounds plausible to my thinking, in line with the comments above. A worthy project - the world needs more R2Lovells in it!

I shoot an R2 Lovell and a .22 Maximum Lovell and love 'em to death. Brass was always the wildcard for me until I lucked into a healthy stash of it thus allowing me to preserve the couple hundred Jamison .25-20SS cases for .25-20 use. But be not dismayed about the expense of original brass because you can swage it out of .223 brass - you're merely swapping time/labor in exchange for $2-5 apiece for original brass, and it's stronger brass IMO.

I recently acquired yet another .22 Hornet so may shift gears with a project that was slated to become a Hornet and make it an R2 Lovell instead. I don't need a 5th Hornet but do need a 3rd Lovell! If you go the route of R2 Lovell and buy a new reamer perhaps I'll in turn rent it from you to help you defray the cost.

Any of you professionals have, or have a connection with a 22 2R Lovell finish reamer.  Currently waiting a call back from Clymer.   
Seems there are several people interested in resurrecting the caliber.   

Thanks