I was waiting for the situation to be resolved to give an update, but given how people have started chipping in again I thought I'd share how things are going on my side:
Mike finally replied and told me the manifold was on it's way, but wasn't able to give a delivery company or tracking number the multiple times I asked, let alone an expected date of arrival.
After some back and forth I asked Mike for a refund, and to his credit he accepted and told me he would make a bank transfer the following day. That was 2 weeks ago, I still haven't gotten my money back and have sent 3 emails that received no reply. So yeah, not great.