New Owner, Low Serial Number?

Hey all! Finally joined the club. Was at the LGS yesterday and picked up a used CRB. Just got done taking it down, seems pretty dirty everywhere so I'm about to have some fun giving it a good cleaning. I came here and started browsing around for tips/info and saw the sticky about all the upgrades. It looks like owner of mine had none of these done. I kind of wanted to know how old the gun is so I finally found what I'm pretty sure is the serial number (starts with TDIXC?) and mine ends with 0091. Just wanted to see what advice y'all had! I'll be out of town this weekend but plan on giving KRISS a call when I get back and hopefully swinging by their office next week.

Hmm, I guess Kriss canlet you know what updates you need. Does it have the green recoil buffer?