Shocks Problem

I have a little problem and I need some advice. Yesterday when I changed my braked I got a little surprise and found my right front shock is totally loose and I can move it around with my hand up and down left and right, there is about a 2cm play. I can’t even tighten it, if I try turning then the whole shock just turn with it even when I am holding it. I don’t know enough about this to know why this happened. I have not been 4x4 for about 2 months and last week I noticed a knocking noise when I brake or take off and I would assume that’s the shockie moving when it’s not supposed to.

The brand is Rancho and after reading all the bad comments about everyone on here should I just get 2 new front shocks or just replace the broken one? If I can buy just one?

How long can I drive around with the busted shock? I have a camping trip planned this weekend up the beach can I go without fixing it or should I do it ASAP? The other problem I have is that I am moving overseas for 6 months in about 3 weeks and when I get back I want to put in a 4 inch lift and then I will have to replace all the shocks anyway, so if I don’t have to replace it ASAP then it will save me buying a shock now and do it all when I get back

Thanks in advance…