We need two good goaltenders. If we trade Murray, we need a replacement. If it were merely about money and cap space, I'd probably budget enough for the goaltending position to be able to keep both Murray and Jarry. But it is not solely about money, as Murray (or Jarry, I suppose) is one of the few tradeable assets we have. And we might be able to either get something we need in return, or deal him along with something we must get rid of (or ideally both).
I think if we trade Murray, we should be able to save a little even if we go out and get another able goaltender to partner up with Jarry. Anton Khudobin would be a solid option, if relatively cheap. I like the idea of signing Laurent Brossoit.
Anyway we slice it, we need two solid goaltenders.