Hello! I am currently working on a new option for manufacturing these. I will be stocking a limited supply of custom parts (such as this coupler) to ship out to people like yourself! (I appreciate the support!!)
I will reply here once I have some available, which I hope to have by the end of August. In the case you can't wait for that - check out JLCPCB.com ... they have a great metal printing service with a fast turnaround, but potentially long shipping times. I can't personally vouch for their 3d print quality but I've heard great things, and I have had circuit boards manufactured through them in the past that were absolutely fantastic.
Thanks again for your support!
Bryan