SPX is the current marking on their SP10 lowers. I just bought one of the PX and called them to verify. SPX marking built in 2024. Doesnt mean it isnt the older SPX, but the new models have the same marking.
That being said the barrel on this gun does not appear factory. I would call Seekins (like i did) give them the serial number and they can give you all the information. If that is a builder kit with a random barrel its not a great deal imo.
I paid 2100 for mine, and its an absolute hammer. Got it about a month ago.
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