the problem i have with the one in the uk is that IMO it's mouth is a bit to low down the pillar. 
 
even the one that was made in the states after i couldn't supply the demand from the mr2oc forums is too low IMO. the opening needs to be higher up the pillar for better air catchment. 
*this is my opinion on looking at wool tuft tests done on the aw11*.. 
 
not the best pic, i have better somewhere on a hdd. but this is an idea of the last one i made.


 

Johhny,
 
have u tried google. a couple years ago I paid $150 AUD from a company in the US, but because I had a brain fart, I order the drivers side (passanger side) for us and I have not been able to locate the site again, but maybe u might stumble accros something? if I had ur skills id make one, but I tried to make a ducktail wing and engine lid, I failed hard
 

I've seen the side scoops on Google. Dont tickle my fancy but that's just me.

Johnny, i really need a damn snorkel 😂

just wait man.  haha