I know this is hard to hear (and my bf and I were long distance for 2 years so I've been there) but, if it's meant to be it will be. It's not easy and there will be days you wonder why you thought LD was a good idea, but you will both be so much stronger when the distance piece is done and will have an amazing appreciation for each other. Try and stay positive!
As for the sleeves, I'd wait. If you buy it now you will just be thinking about the distance more (and if he's into it, save it for a surprise!) I bought my bf a cheap one for us to use together, but he wasn't interested. He's not into toys for him. Talk to him and see if that's what he wants or if he'd rather you save for something else you guys want to use together.