Anyone know where to buy them? The hole is different size on the sock than stock bambu. Cant find them anywhere, not even E3D site.
AliExpress should be able to help.
And if the hole fits over without sticking over the end of the nozzle it will be fine 
The critical part for the heat is not the nozzle - here the sock only helps to keep the stick plastic away if there is a messy build up happening.
Looks like its a standard bambu sock that stretches to fit. Mine has been used for so long that the hole was permanently larger due to the heat. 
What ???
Are you trying to say those silicone socks Bambu sells won’t last forever and won’t stay in perfect condition with lots of use ???
Outrageous to sell consumables without a lifetime warranty…
I somehow had the suspicion they should fit as the ones I ordered so far all managed to stay on my E3D.
Glad you worked it out with good results!