^
I believe Dan refers to the discrepancy between the 3 dates : movement 1955, case 1963 and engraving 1968.
It's a pity if this is a franken as I find it very attractive !
First, I would try what Gatorcpa recommend and checked on the IWC forum.
If there is still doubt, and ultimately, if the seller is sure of the authenticity and you confirm you will buy the watch if all legit, you could ask him to get an IWC extract of archives (300euros) ?
Thanks. There were no movement photos and almost no description, that's why I got it at a humanitarian price. I took into account that it could be a franken, I was bidding as a usable watch - having the maximum amount. I took Gatorcpa advice and already posted a query on the IWC forum. The important thing is that it is not repainted, and maybe it will turn out not to be a franken, then I will win double.