For about $650, you can buy a Rigol DS1054Z and a DG812 both of which can easily be hacked up to DS1104Z / DG992, all the info is here in the test equipment forum.
I have recently bought an MSO5074 for $999 but I refused to pay nearly half the cost of the scope for the LA probes. Some here have x-rayed the official probes and reverse-engineered them using the same (1 GHz) ICs but the cost is still too high IMHO.
Being a masochist, I designed my own LA probes for the MSO5000 and
the thread about it is here. I'm toying with the idea of having a bunch of them made but fear that I will only sell 3 of them and drag my already severely damaged life savings down even further (my 401k is down 28% from it's high in Feb). If you can do 0603 SMT work yourself, I will likely be ordering more PCBs in a couple of weeks.