I would like to find a box or two of 8x57 JR ammunition. If you have some you can spare or know of a place selling some please let me know.

I tried for a while for a drilling and had no luck. I ended up buying some newer 7x57 R and fireforming.
One thing I found is that the 7x57 wouldn't fit in my chamber since it was so tight. There is a very slight difference. I simply used an 8x57 reamer in till it just polished the breach end of the chamber and it worked. Only removed a couple of thousandths of the rear 1/2" of the chamber, which was unnoticeable. I have tried in a couple of other guns since and those chambers readily worked without reaming. The original one was a high quality Berlin made gun known for exacting finish and it apparently had a minimum chamber.

The 7x57R is based on the M93 head size, whereas the 8x57 IR is based on the M88 head size. You might find what you are looking for from suppliers of S&B ammo. Handloading is an option and 8x57IRS cases are the proper head size.
Mike

Thanks for the information. I found a box on Gunbroker. Price was crazy but at least I found a box.