I would like to learn the whistle which one should I start with I would need to buy in mail order so how will I know what I will find easy to play.
any hints.
You could try Big Whistle or The Whistle Shop Happy whistle buying! 
Big Whistle is good you should definanatley find what you need there and it is in the UK.
Forget about the whistle… I want to know about the Duo!
Maybe it’s one of them there new fangled pump up implant gizmos. Certainly sounds entertaining anyway. 
Crazy crazy crazy…
Many will disagree perhaps but go with something cheap and cheefull to start with. You never know, it may not be for you and you will not have had to lash out to much of your hard-earned.
Personally, I prefer the Clarke. It is fairly forgiving, easy to blow if a little heavy on the breath. This in itself can be good as it teaches you good breath control. Nice mellow tone too.
When you get more into it, I’ll make you your very own! Check out my website.