The problem you face is called "the statute of frauds
This is a law that requires all contracts that last a year or longer to be in writing.
You have to prove that (it becomes an element in your case) if you want to sue to collect.
What you describe...you did it right. You had a contract, in writing, and a set end date for the contract.
So you have a claim...but you need that contract.
Now...if you sue, you would be able to have power of "discovery"...so the court can order him to produce.
SO this is possible. You have a contract....even if he lost his copy, if he would acknowledge you did have a written contract, that would satisfy the statute of frauds requirement.
Then this turns into a basic contract law question
And what you describe? You have a great case.
With a few notes
1. If he is in CA, then CA is the place you will need to file this claim. With you in TX that can present a challenge. Possible, sure. But you will need to find a lawyer in CA to file this case for you.
2. If he claims that there was no contract? That may be tough to overcome...you could certainly present evidence to the court to try and impeach him...or perhaps if there is someone else who knew of the contract, they can testify. But you will need to show the court that there was a contract
BotXXXXX XXXXXne...if you had a written contract? You can enforce it...but you will need to prove that there was a contract.
Let me know if you have more questions..happy to help if I can