Can a convicted felon become bonded to become a real estate salesperson in the state of Mississippi?

I doubt it but only an insurance broker would know - some companies will write insurance when others will not. You have to find WHO is willing to write the policy.

Bonding is not the issue, getting the real estate license is the main issue. You will need to get pre approval from the board of real estate to even sit for the exam.
They will review what the conviction was for, how long it was after the conviction and lots more.

For the bonding there is a Federal program to give temp bonding. Beyond that check with insurance agents for bond requirements