Mark IV . Rubber ring ??

Hi folks,
I’m new to this forum so I hope I’m in the right place, and that someone can answer my question!!
I love the Mark series ,and a few months ago I bought an omega mark IV (176.009) that is in need of some TLC. The seller admitted to shaking it a little to much in an attempt to get it going. I discovered that the little to much had caused the rotor to come away from the center “bearing”. !! However after popping it back on it is already running like a dream, really it needs I good cleaning ( and maybe a new glass...the never ending question... . ummmm not sure, the scratches are growing on me)
Also it is in need of a new rubber ring between the outer and inner case.!!! At present there is enough sticky remains to hold it in place but once I’ve decided what I want to do with it , it will need a new rubber.
So my question is can someone give me the part no. or maybe a contact or even has a spare laying around????
I’ve included a photo to show what I have left and clarify the part i seek
I’ve been wearing it for two months now and it’s a great watch!!
Many thanks

Hi,
Maybe someone has acces to the Omega extranet?
Part number that might fit the bill for the MK IV at cousins is 088NS5091 for a black seal o-ring. or the 088NS0039 which is stated as a flat seal..
there is a 088NS5091 on the bay just now for 19,95 that is sold as a "crystal ring".... in Germany, Berlin. unfortunalty the pdf's do not allow a further search.

an 088NS0039 is sold for about €35, also in Germany..

One of them also could be the case back ring...?

I bought a new glas for my MK 4.5 a couple years ago. there also was the black rubber ring stated as the glas ring. My watchmaker told me there is no rubber ring under the glas so I did not use it then, and I actually think it might be the case ring.
The Crystal gasket for the 176.00(0)9 for example is the 098EG0028
for the money these two would be a good start I think.
Maybe someone else can point you in the right direction with the number?

cheers and good luck, 👍
Tom