Stumbled across this thread and felt the need to register all of a sudden, so here goes, my first post.
I have one of these exact rifles, and it's an awesome rifle to shoot. Mine doesn't even have bases for a scope, I just use it as is with the original iron sight, works perfectly for driving hunts. The 1910 was only made in 9.5x57 M/S (a.k.a. 9.5x56 M/S, a.k.a. .375 Rimless Nitro Express 2.25". Not to be confused with 9.5x57 Mauser!).
You should definitely try to get this rifle going again, if you or someone you know handload, this calibre is neither hard nor expensive to make, once you get hold of the right tools. CH4D has them, RCBS also has (or had) tools for this caliber, that's what I'm using. Just make sure that it is in fact a 9.5x57M/S, a lot of these rifles were converted due to the obsolete calibre.
Your best bet is to form your own brass from 30-06. I've tried to use all kinds of cases from the x57mm family and it might work for you but chances are you'll end up with headspace problems, as I did. When using the 30-06 you can get the case shoulder just right for your rifle. The 9.5x57M/S is NOT in the x57mm family, although it is similar.
Use a case that has an even brass thickness in the wall of the shoulder and body. I use Lapua/Sako, or Sellier&Bellot, but I don't know how common they are where you live. I've heard that Winchester or Remington works perfectly (can't remember which), but they're not that common where I live so I've never tried them. An even case wall will prevent bulges on the case neck when calibrating.
Cut the case to something like 58mm. Use a .375 Neck expansion die to widen the case mouth. Run through the 9.5x57 calibration die. Trim case to 57mm. Voila. Mine works right from the start, some people recommend fireforming but I never had to. Makes no noticable difference for me at least.
The Mannlicher Schönauer rifles requires a round nose bullet and correct cartridge length to feed correctly when loading the magazine to full capacity. Factory cartridges were loaded with 270gn bullets.
You could use pointed bullets if that's cheaper, but you might not be able to load more than one or two bullets at once. My magazine locks up completely when loaded with more than 2 pointed bullets.
I recommend Hornady 270 RN, which is very similar in shape to the original bullet. If you want to use a premium bullet, Woodleigh makes a round nose in 270 in basically the same shape.
When it comes to loads, there are some information to be found out there, but not much. A good place to start is to find some loads for the 9.3x57 Mauser and start low from there. I've only used Norma powder and I am still trying to find the perfect load. I have developed some more than acceptable ones but not quite reached the performance of the original cartrigdes yet. Original cartrigde delivered 2250fps in the rifle and 2150fps in the carbine.
My rant is now over. I have a bit of a passion for these rifles, sorry for the barrage of information.