Thanks for your useful replies everyone!
I realise now that I was labouring under a confusion between FURLING systems (for simply quickly getting the sail out of the way) and REEFING systems using furlers as part of the mechanism (for safely reducing sail whilst out on the water). This is obvious to me now … but then I am a great beleiver in the maxim that “the only dumb question is the one you don’t ask”.
So there is a nice choice of modest cost solutions: between the helyar and aeroluff systems combined with a high-tension furler. Interestingly the helyar system (mk1) comes out little more expensive than a quote I had for a new “yankee” jib. For anyone looking at this in the future here are the relevant links: http://www.aeroluffspars.co.uk, and http://www.flexible-reefing-spars.co.uk.
Then there is the sightly (havent’ been able to find out quite how much) more expensive “cadillac” system by Bartels described in bob’s link, for which I can’t find a sales link in English just now.
Sadly a reality check with the bank balance indicates that I did indeed fall in love with a more expensive boat than I intended to buy, but I’m absolutely sure its a good purchase in the long run, so plan B is to ask around in the club for an unwanted enterprise or mirror jib which I can hoist should unpleasantness arise, go ahead get the reefing points put into one of my mains and start putting money in the piggy bank.
cheers for now