Why do you need so many? 40 floppies at 1.44 mb are only 57mb and one memory stick will easily fit them all on. Personally I like Sandisk memory products but if the items are critical and irreplaceable I would also keep at least one backup. An example click hereclick here
Got a dabs value aluminium one a few months ago. Quite happy with it. 2gb for under £20 at the time but memory has gone up in price but they are great value. The Dabs ones are a little slower than more expensive branded ones I have had but it by far looks better and was a heck of a lot cheaper. An alternative suggestion I have for you is CF cards. Damn near indestructable. I remember seeing a video of a group of people showing how tough they are and ran over it in a car. Dropped it off a building and at the end of it all washed it. It worked still however they did have to use novel methods of getting the data out.
Also CF cards are cheaper in most cases. I have seen computer fairs offering batches of older ones (mixed bags of 10 chips) for £5. You could end up with anywhere from about 128mb to 512 in total.
On that note PCA did the same sort of thing for the magazine about 2 years ago if I remember. However not at home so cannot trace the issue but Im sure FE probably knows considering he was able to tell someone about the weather on the day they joined up.