How can I post my own version of a published SPIE paper on arXiv?
So is there a way around it for me to submit my article to arXiv?


It's reasonable for you to ask SPIE for permission to post the paper to the arXiv (under conditions (a), (b), and (c)).  They might not grant permission, but it can't hurt to ask.  Even if they deny permission, at least you've given them feedback about what authors like you want.

One possibility is that they actively object to posting on the arXiv.  In that case, you are probably stuck.  Another possibility is that they don't specifically object to the arXiv, but don't want to authorize arbitrary websites they are unfamiliar with or other websites they object to.  In that case, they might grant you permission.  If they do, then that should suffice for the arXiv administrators.


  If not, I think I can surely post it on my own website, right?


Yes, assuming it is controlled exclusively by you or your employer.  (That's true for most people's websites, but it could fail in unusual cases, for example if you are treating a social network page as your home page.)