So, I did the same thing. Now I did notice that it did not come with an amd backplate just an intel backplate.  So this should mean that it is compatible with am5. I have not tried this yet but if you have let me know here.

Me now. Same situation. Can’t find the way to get the AM5 Upgrade Kit. 

So the submit button is having issue with the hanbo so i selected another one of my devices to submit a ticket for it and once it went to the next step i put in the serial number for my hanbo and got ahold of customer service and they are sending 1 out free of charge.

@Razer.Speedcr0ss @Razer.Zionzedd @Razer.Aero ? :)

I just Received this response from support

“To set your expectations as well, currently, Razer don't have available spare parts to Razer Hanbo device. However, you can buy from a third party seller near from you”

Struggling to find this part in Aus

@Shazlow86, It took them a few days to find the part for me and got it sent out and received in 24 hours. So, I’m guessing this must be for their US warehouse that had it. Just an fyi. I did change this out and installed it today and it seems the only difference is the height of the screws. There is a VERY small difference for height between AM4 and AM5. The original bracket will fit so the only thing that really needs to be looked for is the screws. Now, with all the stuff I have from old builds and miscellaneous parts I did have a really long philips head screw that would fit into the board. So before install I cut this down and added some plastic spacers and was able to make it work that way as well. I was only going to do this as a last resort, but this does work and holds very well. Again, as a last resort you can easily do the install. But I would still talk with support to have them locate it. Make sure to ask for the AM5 Upgrade kit that THEIR website told you to contact them for.

These also seem like what razer has that was sent to me. Cheap enough to try out. I cannot confirm if any of these work.

Amazon.com: Cool Water Series Kit, CPU Cooling Fans Bracket, Cool Water Series Accessories Kit Radiator Stand System Mounting Heatsink Holder Back Plate : Electronics

Amazon.com: Fit AM4 AM5 AMD Mounting Bracket Kit forfor ID-Cooling ZOOMFLOW 240x ARGB CPU Water Cooler 240mm 5V : Electronics

Were you able to figure out if this works? Was going to order the hanbo but would be in the same boat. Would just order that with it