https://thegreatmodel8.net/

i bought a model 8 last year from a friend of mine, great shape and love the rifle! with it cam a Marbles r6 Flexible rear sight with original box, paper work and replacement apertures. i can not find a lot of info on this sight but my friend told me it was bought with the rifle and for the rifle though it has never been put on it. he also told me that it was very collectable and hard to find. can anyone confirm that this is the correct peep for the model 8? i am not interested in putting it on and will eventually sell it to recoup some of the $$$ i paid for the rifle.

Yes, R 6 is the correct Marbles for the M-8. Should have sold for about $4 back in the day... might go for a bit more then that now.

lol no doubt a tad bit more in value now especially as mine has all the original paper work, box and apertures. i am not sure how to get it to release in to the up right position though?

Sir,
You do have a desirable sight there. There is a small 90 degree looking latch that when pulled on,will release the sight to the upright position. It's in front of the stem, between the mounting bracket and the sight stem itself. I hope this helps you. And yes I'm interested in buying your sight. My email address is in the signature box below my name.
Thanks for your time ,
Roger

Here you go, this is the release Roger is referring to.