Yes, I know Numrich has tubes (nobody else seems to have any in stock) but I figured if I could get it apart I might be able to save the owner 30 bucks by getting it open to see what was wrong inside. It belongs to the guy who's rebuilding my uncles 1928 Model A Ford roadster. If I could get at the guts of it I'm sure I have a spring around to fit it.
looking at mine, it appears that the pin that locates on the outer tube is brazed, welded or soldered to the inner tube. if you mess up the inner tube trying to get the pin out, you will end up having to get another inner tube assembly anyways. now, my suggestion would be, to try a dremel tool and very carefully cut the opposite side of the pin and then support the inner tube and then very carefully see if you can drive the pin out. it appears the pin is what holds the end plug and the spring in the inner tube. now if you make it this far and get it apart without destroying the tube, find a wooden dowel the that will fit inside the tube and use it to straighten the tube. also clean and lightly oil the inner tube and put it back together and see if it works.
if this doesn't work, then you will more than likely have to just go ahead and buy another inner tube assembly. but it might work.