What do you want a quad LMB for with Sky Q? You only need 1 Sky Q silver box to then connect your second sky q box to (assuming you need multi room in your caravan!) so only 2 cables needed.
All you need for Sky Q is a new wide band LMB. When my home Sky was upgraded to Sky Q the engineer was more than helpful - put a hybrid LMB on my home dish (so I could run both Q and an old Sky+ HD box for freeview in a third room), and gave me a wideband LMB for the van dish, all for no extra charge.
As for the dish, I just use a regular sky dish on a tripod- cost about £50. Tuning is done via a sky signal finder, at a cost of about £5 IIRC. Takes all of 30 seconds to find a signal, I can do it by the sun these days
But if you've got £2K to burn then get this instead!