If the crack ends at the screw hole, it shouldn't go any farther. One possibility is to grind or drill out enough at the front edge to use a TIG welder to close off that end of the crack. By using a heat sink, that can be done without getting the rest of the receiver too hot. Make sure the welder uses mild steel that will take bluing, then polish the weld down and cold blue it.
I would check with a gunsmith for a first hand look before doing anything, though. Go by what he says since he is looking at the gun.
NOTE 1: The above assumes the receiver is steel; if it is alloy, fageddaboutit!
NOTE 2: The above should be OK on a .22 receiver, but I don't want folks saying I favor welding cracks in receivers of high power rifles. That is a whole different ball game.
Jim