There have been several Luger clones imported or made in this country, including one by Mauser. People who claimed they would sell like hotcakes didn't buy them in droves.
The simple fact is that a Luger clone, if made properly, will cost a good chunk more than an average decent Luger. With the real thing selling for $500 or so (East European import), who is going to pay $1500-2000 for a copy?
As to making a Ruger .22 work with 9mm, the idea is impossible. A stiff spring is not enough, you need breechblock mass. Attempts to use blowback with a light breechblock have always failed, since the spring has to be so stiff the gun can't be cocked without some kind of disconnect mechanism (like the S&W .35 and .32 pistols based on the Clement design).
The Luger is a locked breech, recoil operated pistol, just like the Model 1911, though the approach is different. If one wanted to make something like the Ruger .22 in a larger caliber, a better approach would be use the Nambu locking system rather than the Luger toggle. (FWIW, rumor has it that Ruger actually built a "Rumbu" in 9mm, but it was not a practical production item and, with the company selling all the guns they can make, not exactly necessary.)
Jim
