Soviet Special Naval Scouting (Spetsnaz) badge

[billy]

Hi gents I know this is not British but has kindly been identified by Arhemjim, as being the above, as S/F collectors have any of you any information on this badge useage and are original badges from this unit common, apparently lots on ebay but copies or real I have no idea?
The badge is nicely made the chain especially so looks to be of bronze material, hope you can help, apologies if I shouldn't have posted here (its in foreign badges) but thought you may like it also and information may well be within this group (yourselves), Many thanks billy