LS - I think you may well be able to get a sleeve for a long-haul flight but you would need to be assessed by a lymphodema nurse/lymphodema clinic (or however this is set up in your area). I was told that anything over around 5 hours would meet the criteria for having a prophylactic sleeve.
It is important that you go to the clinic to be properly measured. A badly fitting sleeve may do more harm than good. It's also good to have a baseline measurement done anyway. If you have any problem getting an appointment then may I suggest that you use the 'ask the nurse' facility on BCC. They have nurses that are extremely knowledgable on lymphodema who would be able to advise.
You may have already have a bracelet/band warning about lymphodema risk but these are a good idea to wear on holiday too. Basically, in case of any medical problem it warns clinicians not to use that arm for needles, BP etc.I've got a mauve silicon band from this company (they also do pink).
Janice - I'll take a look at the site. I have a lot of difficulties with my sleeve and have finally found one that seems okay. £22 is really good as my sleeve costs around £60. Won't chance anything yet though as still trying to get things back to normal.
Thanks everyone else. Jax I did wonder whether the company my sleeve comes from would just allow a purchase without a prescription.
Four sleeves a year is okay if we sit in our houses wrapped up in cotton wool but if we want to have a life then it really isn't!!!