Hi Nick,
Maybe I'm a cheapskate, but when I misplaced/lost the proper straps just before a trip to France last year, I ended up with a couple of leather trouser belts fastened together lengthways to make each strap. It was OK and so when we visited Devon last weekend I bought some leather XXL belts from a stall in Tavistock indoor market in case my originals don't turn up before LMC in July.
We have always use the Samsonite type suitcase, rather like the one in the post by David of SW19. If you look at his post you will also see that he has mounted a high level brake light on one of the cross pieces of the H strap. I did the same with an LED light from ebay. I seem to recall that Dave Wellings posted a guide to how he did it on here
http://www.talkmorgan.com/ubbthreads.php/topics/40612/Trads_High_level_brake_light_w#Post40612Best wishes for the trip!
Malcolm T
