There are now a number of lines: Prps (made in Japan), Prps heirloom (made in US) and PRPS Goods & Co (China).
The vast majority of PRPS are not selvedge, and those pairs that are, are mostly not purple. The first few seasons one rinse Impala selvedge did have purple selvedge, but most from then on didnt.
Also, the impala fit is discontinues, and PRPS has always been about the distressing.
What website did you order from?