How do I sell my business promissory note?

Hello,

In need of advice, any is appreciated.

I sold my business last year for $400k plus earnout, 300k was paid in cash, 100k was in a prommisorry note at 8% amortizing over 4years. The earnout was for a year.

It's been a little over a year. the promissory note has $79k and 3 years left.

I have a business opportunity and could use the lump sum.

Are there buyers/investors of these notes? I would assume so. All I find online are firms that buy mortgage notes secured by the home.

Thank you in advance.