If you have a lathe or have access to one you might be able to turn one of the ends of the hinge pin down to correct the angle.? That side will drop by the amount you take off the radius so you will want to carefully measure the angle and calculate how much you need to remove.? The original pin is held in place with a roll pin so it wouldn't be too difficult to make one, rather than risking the original.
There are some limits to how much of a correction you can achieve this way.? Turning the pin down a lot will make it weaker; and the other end of the pin must have enough "slop" so it can rotate through a small angle.? Based on John's permanent fix #1, I have to assume there is enough free play to accommodate at least some angular displacement.
That's not an ideal solution by itself because it also introduces more play in the hinge.? To address that, you can use John's grub screw suggestion.? Drilling and tapping 2 or 3 holes can be done with a hand drill and tap.? The grub screws also might assist in correcting minor alignment problems on the horizontal axis.
The advantage to this approach is that you can always go back to the original condition of the saw, since the casting(s) have not been substantially altered to the point where they're not compatible with the OEM replacement parts.? Plus that way you have a hole to apply lube to the hinge :).
Mark?
