Our market space is finite and relatively small (~200). We can charge for license (3- to 5- years) and monthly support.
I don't know of one you can just download, but it should be fairly easy to make one. The questions you need to ask are:
* What is your value per customer (license + on-going maintenance and support)?
* How much does it cost you to service each customer? (Variable operational expense)
* How much does it cost you to run your company regardless of the number of customers you have: software development, accounting, sales, etc.? (Fixed operational expense)
* How much of your market can you capture?
Then it's just comparing revenue to cost. One other thing to consider would be, how do the customers in your market segment? Are they all the same size, or are they a few big players?
In my experience, in most cases the financial model example you mention here, would need to be purpose built to capture the actual specifics of your business. It is hard to be generic as there always are some little specific element, you have to be able to handle.
I have lots of experience in building such spreadsheet models, to if you are looking for a template to use as a starting point or you want to get some hints on it, feel free to set up a call. I would be happy to help your understand your business case.