There is @LED_Seedz who is quite active on OG with numerous tester grows. Although, I do not know if he’s using the Strainly platform. In the past, grow-legal.com was the exclusive distributor although the US shipping option has been disabled for some time now.
@BogSeeds is also an OG member. They are on Strainly at https://www.strainly.io/en/pat
@Swampthing, listed as “The Danky Bank” on Strainly at https://www.strainly.io/en/swampthing