Sorry to be the bearer of bad news but you probably may already suspect what I’m going to say.
There are no other vendors apart from the official H.P. website.
Managed to get tickets for opening week. Tickets opened for booking about 6 months in advance. Took all day with 2 people on separate computers to book tickets but DEFINITELY worth the effort. Amazing sets, amazing atmosphere and lots to do and see.
Wont tell you how old I am, you might think i’m really sad but then again there is a little kid in all of us just waiting to get out!
I’ll be amazed if you get tickets via a different vendor.
Good luck. Its worth it. (I’ll be going again at Christmas.)