I've always thought a minimum CPC service contract holds a weaker argument today than it did 10 years ago. Further, bundling the lease with a minimum service allowance exclusively benefits the dealer. I've landed a lot of net new deals during our county's SIP order from DMs upset that they've been paying for a lease payment + service with a minimum allowance for a machine they've hardly been using this year.
As for your price model: everything's turning into subscription services for businesses and DMs/purchasers are more familiar with this type of price model than they were 5 years ago. Microsoft Office, Adobe, Salesforce, etc. are all just as essential and common in companies as print, and they usually pay a "$X minimum or Y% of their subscription per year for upgrade assurance, service support, remote assistance, etc". Sure there's a difference between hardware that consumes ink/toner than a simple software license, but the resources we have today give us so much data that we can drill down on profitability without having to worry so much about how many pages a toner cartridge will yield or how many parts will fail out of warranty.
The hard part is convincing old heads in the company that changing from the traditional CPC billing model to a SaaS model isn't as risky as they think. The second hurdle is presenting this a la carte service to customers and convincing them it's in their best interest to buy apples instead of oranges.