I'd keep both goalies unless there is a possibility to acquire a real good no. 1 in a trade.
Spence could get a 3-year bridge deal and sign a long-term one like Saros did as a 28 or 29 year old. If he is not ready for a starter goalie job, then just trade him before giving a long contract. Bob on the other hand probably could play a couple of years after the current contract and I don't think he'd want too much money because he already earned so much.
Of course the situation might change if they play badly in the playoffs but to make any change, it needs to be an upgrade.