Fit a Honeywell RDR 2000 weather radar if you go down this path (I think this would fit although would need some other avionics to interface?). I wouldn't want to fly around this area without a radar IFR/IMC. I would probably want oxygen also to get above the weather a bit.
Make sure the pilot is experienced and competent, don't just go for the cheapest. It isn't the kind of flying suited for an enthusiastic amateur.
With regards to range etc I am sure you can work that out.