In response to several people asking what brand they are, I reached out to SOR and here was their response:
"Hello, We have these made for us from an overseas manufacturer. Specter Off Road will not disclose our manufacturer."
Not the most helpful, but I didn't expect to receive much more from them (which is a shame considering how much money I've given them)
For clarification, the parts number I listed is shown on SOR's site as +0.020" that is equivalent to +0.50 mm which is stamped on the piston head. I left them in the box in my garage that I won't be back to until Friday, I'll post a photo then.