To get initial 10 users for SaaS - I will not promote

I am running very successful 2 biweekly newsletters that are distributed among tech communities and have a combined audience of slightly over 275K. I run advertisements through it but smaller SaaS companies usually can't afford that . I am thinking of running another revenue stream and model where SaaS products that are just beginning their journeys offer a FREE 12-month subscription of their lowest paid tier to users. And a small fees per user who signs up payable to me. They will define how many signups t