Aha- Evilbay is your best bet for scoring one at a reasonable price.
US M69s were 'appropriated' by both the Israelis and the UK during the 1970s- The UK ones have big rubber pads for the rifle buttplate to catch on which can be removed with ease.
Generally the UK and Israeli 'Flak Jacket' or 'Flak Vest' (search terms!) come in a good deal cheaper than the M69 as they don't have the 'cachet' of being Vietnam issue.
Also of note is that M69s come up large- and get a bit baggier with age and use- so my quite battered Medium fits my very-definately-Large 43" chest. That's with the nylon filler still in- remove the filler and they get bigger again.
SOF have a bad history of 'creatively mislabelling' repro kit as original, selling heavily soiled/damaged gear at Grade 1 Unused type prices and generally being a bit airy-fairy on delivery times- their chinese made repro Vietnam gear used to be horribly made and horribly expensive: it's now much better made but still horribly expensive compared to original issue.....
But sometimes- and I hang my head in shame at the thought- they are the only place you can get something at short notice. And then my wallet goes to hide under the sofa
