At last I found what looks like what I need on ebay http://www.ebay.ie/itm/150762273467?ssP ... 1423.l2649 - coarse match rods with sliding reel seats are quite scarce and even harder to get shipped.
Last year I fished maybe 4 or 5 times using Mikes polypropylene line using my 10 ft rod. Allthough a bit rattly going through the rings ( this should improve after serious use) and a little prone to spray the qualities of this as a fishing line far exceed by a country mile, that of any conventional fly line I have ever used on a river. As it floats on rather than in the meniscus it lifts off easily, cuts through the breeze and mends easily.
I am simply salivating at the prospect of using this line on the 12 or 13 ft rods. No doubt it will be a slight challenge to get used to the casting, but having spent many years salmon fishing and doing single and double spey casting I should be able to come to terms with that reasonably quickly.
I have no doubt that the control that these longer rods will give me will improve my fishing immensly and more importantly it should be good fun learning something new ( or is that something old, using long double handed rods

A special thanks to Mike for his advice and help ....