Alumasc beer tap spares

[Redron]

Hi,
I recently bought three king kegs all fitted with the Alumasc tap from Ebay. I have since bought another keg and bagged another Alumasc tap on Ebay again. When I came to fit it it appears the bore of the threaded part is much smaller than the keg aperture.
On further inspection of the others, they have a threaded brass collar/reducer that fits into the keg aperture, allowing the fitment of the tap.
Anyone know where I can get the said collar ?
I've also noticed the plastic nut that screws on from inside the keg are pretty vulnerable to over tightening . Is there an upgrade available ...

 

[Dizzle]

Anyone know where I can get the said collar ?

I believe you are looking for something like this?

http://www.asap-supplies.com/marine/anti-siphon-devices/brass-reducer-adapting-bush-fitting-407514

I think the measurements are 3/4 to 1/2 so you just need a reducer, might be able to get locally in trade stores

 

[Fil]

I can confirm the tap thread is compatible with 1/2" bsp..

the fitting is a reducing bush. be careful as over tightening the tap can result in snapping the barrel as its a fairly brittle plastic.

 

[Redron]

Brilliant, thank you.
Looks just what I need.