Looking at options out there DeSmith could be one ... Anthony Stolarz from Anaheim might be a consideration, so could Cal Petersen ..
Kaskisuo is better than Stolarz. At this point any goalie could catch lightning in a bottle so for all we know Stolarz could be our saviour or a total bust, but you can say that about literally every possible backup option right now.
I don't think the Leafs go with DeSmith. PIT will want too much, there are no guarantees with him (only one quality season on a team where even mediocre goalies typically do well), and the cap doesn't work (and I definitely am not paying the premium required for them to retain). Plus PIT will probably want him as insurance given Murray's injury history.
Petersen is another solid option. Only problem is price. How much are you willing to pay for a 25 year old goalie with a good, but very limited, NHL track record and quality AHL numbers. I think he's worth a shot, but I wouldn't give up more than Petan and Hutch for him, considering all a 25 year old Calvin Pickard garnered Vegas was a contract dump prospect (Lindberg) and a 6th. Pickard had a much better track record than Petersen at the time of acquisition.
We aren't short on possibilities. There are countless options that are all about as equally viable and likely quite inexpensive to acquire. The problem is none of them are anything close to guarantees nor clear cut upgrades over Kaskisuo or will solve our problems anymore than Sparks did last year. We'd essentially just be shooting in the dark and hoping one turns out like we are doing with Kaskisuo right now, because on the surface I don't think any of them are any more likely to succeed as our backup than Kaskisuo at this point.