This will give you some idea of the odds:

5003   1898 Carbines were made, with short stocks, etc. Very soon after production they were called back and restocked.

Around 160+ are recorded.

13 are known @ 118xxx
52 are known @ 119xxx
49 are known @ 120xxx
Everything else is in single digits, but there are apparently significant blips at 125xxx and 131xxx.

Clearly, that (118-120xxx) is where the bulk of them probably occur (SA made arms in batches, based on the quarter of the year, and changing over the stocking machinery) upset only by pulling receivers from the bins using FILO).

The lowest verified specimen is 112864; the highest 134317, giving a difference of 21453 (plus some statistical allowance for not being positive of the high/low) say 22000 - dividing by 5003 = 4.4, which inescapably leads to the conclusion that around 70% of the offerings are, shall we say,"incorrect"!

Joe Farmer says he can positively ID genuine 1898 Carbines. When he makes such an unequivocal statement, I tend to believe it to be accurate, though in the case he has not shared the method with me.

So - it's a crap-shoot.  :-)