replacement Snorkel HEADS

Forum: 

Hi all. Looking at possibility of importing SNORKEL HEADS. they would be "Safari type" (copies) with 3" or 3 1/2" fitting.
Questions are: is there a market for them at sensible prices (probably about price of Southdown heads) and which is the more common size?
Any help would be apprecciated here as I would have to buy in fairly large quantities!
My target price for selling these would be about 30 squids as opposed to 55+ for Safari ones.Also looking at stock of replacement original style grilles.
Cheers