The screw will loosen, usually withing a couple of days with repeated oilings. The on on my 201 took 2 1/2 years, but it is my personal record lol. Another stuck scew loosened after three weeks of oiling and just letting it seep in there. There are spray cans with something that will make your screw freezing cold, it sometimes freez it up, you could try heating it with a hair dryer,... Is it completely stripped? Then you might as weel drill it out, but be careful not to ruin the threading in the clutch knob itself. I don't think this screw is easily found by itself, you might have to track down a replacement clutch knob or hand wheel set some where to get the screw.