Yeh, A nice condition gen bezel for a YM is really hard to find. You can expect to pay around £1000 minimum if you can even find one. If I stumble across one I will give you a shout.
The problem with the YM bezel is that the gen is made of 950 platinum and steel mix which Rolex patented as rolesium back in 1999
On the 116622 YM the entire bezel assembly is manufactured from Rolesium (950 platinum) and as a result the process of manufacturing and finishing a material to even look remotely the same is extremely difficult and costly.
I personally think the current Rep YM offerings are pretty good but when it comes to the 6 dig YM the bezel will simply never compare to the gen as the gen material is impossible to replicate within the budget of a replica watch.
I suppose as a result of this the gen bezels and indeed dials are so difficult to find and expensive making a Franken project on one of these quite a costly one I'm sure