See these discussions with recommendation on how to find reviewers:

https://www.researchgate.net/post/Where_can_I_find_reviewers/1

https://www.researchgate.net/post/How_do_you_get_peer_reviewers_and_if_any_are_available_please_reccomend/1

https://www.researchgate.net/post/How_to_get_early_peer_review/1

https://www.researchgate.net/post/Is_it_mandatory_to_select_some_potential_reviewers_while_submitting_a_manuscript_to_a_journal/1