When Colin (Spanner Juggler) returns from his trip out today, he can post the link that several of us used recently.
These are uprated blades that fit a Series Land Rover , they are slightly too long , but a couple of hacksaw cuts and a little finishing, and they are great fit. A big improvement on the MMC sourced items for very little outlay in terms of both price (less than £10 per pair) and fettling. As they are sold in pairs and most of us need 3 , it is better to order 3 pairs and split the purchase with another owner.
The alternative is to follow Dave W's guide and convert to a later system which puts much more pressure on the blade and therefore wipes more cleanly at speed.