I have a Spanish M1915 short rifle in 7mm, basically identical to the M93 except it has a short barrel, I think around 20"-21". In pretty good original condition and with a shiny bore, I paid $15 for it about 10 years ago, just because it had the body of a fired case stuck in the chamber. I got it out without much trouble. Even with the crude military sights on it, I can keep all hits within a few inches at 25 yards and that's good enough for me. I've considered sporterizing it a few times, but decided to keep it in its original military configuration. The last thing I need now is another hunting rifle. I once sporterized a near-perfect Swede M94 carbine in 6.5x55mm (it also used an action virtually identical to the M93), and later really regretted it - those Swede carbines are hen's teeth these days, and will bring a pretty hefty price if in original condition.
My M1915 has no markings on the front receiver ring, it is completely smooth. When Generalissimo Francisco Franco won the Spanish Civil War in the late 1930s, he ordered that all Spanish military rifles having the royal Spanish crest stamped on their receiver rings must have it machined off. That alone should add some historical value. Most of the M1915s imported into the US ended their careers in the hands of the Spanish Guardia Civil, one of Spain's paramilitary national police forces, which is tasked with performing police duties mainly in non-urban areas of Spain and also on highways.
I agree about the merits of the 7x57mm. It is fully capable of being used with deadly effect on nearly every game species on earth, provided the hunter is a good shot and is using the correct bullet best suited for the game being hunted. With heavier bullets, it provides outstanding penetration on large game. Jack O'Connor felt that the 7mm was the ideal chambering for a hunting rifle to be used by women, and wrote about that several times. But not nearly as many times as he wrote about the merits of the .270 Winchester, which was his favorite. I can't dispute that opinion either. My most treasured rifle is a 99% condition Winchester Model 70 in .270, made during the first year of production. Its only defect is that a previous owner added two threaded holes in the rear receiver ring for mounting a scope. Early M70s did not have threaded scope mounting holes in the rear receiver ring. But it is what it is.