The guide rod that originally came with it might have a black plastic base that fits into the barrel lug. If that's the case, I'd upgrade to one that has a metal base.
The earliest G26's had non-LCI extractors and spring loaded bearings. There's nothing wrong with that, it's just something to be aware of in case you ever decide to put a new extractor in it. The extractor and spring loaded bearing come in two types, non-LCI and LCI. Both must be the same type or the gun won't function properly, so if you change the extractor from one type to the other you must do the same with the spring loaded bearing.
And the early sub-compacts came with adjustable plastic sights as well. One of the previous owners might've changed them, but the original sights may still be on the gun.