CassidyAce
Senior Retro Guru
I would investigate further. Specifically, I would want to know whether it's really the spider that's at fault or whether it's where it's locked to the crank that's the problem. If the spider is perfectly straight but the crank is not, or rather, that part of the crank that meets the spider is not perfectly straight, then getting a replacement spider further down the line will just replicate the problem rather than solving it. The fact that you say that, not one, but two adjacent arms of the spider are out suggests that perhaps the spider is not perfectly flush with the crank or, if it is, perhaps the surface it's flush with is not as it should be, or it might be that the spider is at fault, which is what you suspect. Of the various possibilities, I would want to know where the fault lies before buying another spider.
Have you tried unlocking the spider from the crank and reinstalling really, really carefully?
Have you tried unlocking the spider from the crank and reinstalling really, really carefully?