Bet it's a Wix 51069/Napa 1069/AC Delco PF25. Evenwith the remote oil filter they probably used a std Chevy oil filter.
Wix 1021 does not cross ref, it is a commercial application filter.
I'd take i down to Napa and match it up. Start with a 1069 or the longer version of that filter.
'06 X2 MCX
"I understand why some people may not want to do this the way I have recommended but I can't understand the death grip some people have on a toilet plunger with a hose fitting." -JimN