Omer cayman g.i. camu 100cm needs new rubber bands and wishbone

[Sunken norwegian]

Ordering some spare parts for a big trip but finding out what i need for my Omer G.I speargun has turned out to be quite a task.
My speargun is a 2016 modell. From what i read it is suppose to have a 16.5mm band with 26cm lenght.
Meassuring the curent original band it`s 29cm and 18mm thick. So i was about to order this but then i`m not able to find a wishbone with threads for the 18mm rubber bands.

Is it the same "Threadfittings" for the 16 and the 18mm??
Or am i a retard and i should just order the 16.5 bands? my fear about this is that the treads om the rubbers will be to smal.

Bonusquestion: Is it possible/recommended/ment to be able to to add an ekstra rubber trough the forward hole in the muzzle? Omer metions nothing about this in their spareparts description.

I`m really lost here and any help would be much appreciated

Kind regards
Ivar from Norway

 

[Diving Gecko]

Hi Ivar,
Sorry, it is late where I am so I will give you the short answer which will be puzzling. But drop 16-18mm rubber and see if you can get some Primeline 14mm Small ID rubbers. By spearos much more experienced than me they have been proven to work better.
Google it, spend a bit of time over on spearboard.com and you will find out why. Now, getting them to you in Norway might be a bot of a challenge but I did find a few online shops in Europe who carries them (Vidrax, apneashop.it and edive.gr) though at double the prices of what they cost in the US.
Upload a pic of your muzzle so we can help figure out what you need to rig there and if it makes sense to add two rubbers.
Also, how long is your gun and is your shaft notched or does it have shark fins?