Singlespeed Conversion, Help Needed Please

Can I get a conversion kit that would fit onto the freehub thats on the bike now? At the moment there is a 5 speed one on there but I would like to keep the old 27x11/4 wheel if poss.

Well, we're only going on what he says. Yeah they may be rare, but it's what he says he has.

However this is really arguing semantics. i'd recommend that he just takes the derailleur off and runs the best combination of chainring/sprocket that gives him the best chainline.