ride height sensor part #?

[adtubman]

Been browsing here for years but rarely have needed to post due to all the great info! My ride is a 2003 H2 SUT. I am having a problem with my left rear ride height sensor (pretty sure that's the issue at this point), some days works some days won't. I would like to replace it. I am being told by my (very young) gm mechanic that the part has been upgraded and requires the sensor and the redesigned harness (part #s 15124930 and 88964339). I am wondering if it might be possible to just replace it with an equivalent 'original' sensor without getting into the upgrade. If so, I guess I would need to locate the part but I'm not sure if the part number above would be good for the 'old' sensor or if that is just the part number for the upgraded sensor. Anyone have any info on what the 'original' left ride height sensor part number might be and if so, any suggestions on where best to try to locate an original item (think I saw a contact for parts on the forum at one time)?

Any help is appreciated! Amberlyn