I just purchased an Instep Pathfinder pedal trailer from a thrift shop but it is missing the coupling that goes to the pulling seat. I thought I could purchase it from Instep directly but while the description link is there, there is actually no way to purchase it: https://www.instep.net/Product/Acces..._Kit_25-PF001/
I found a couple of other couplers that might do the trick on Amazon, but I don't know if they are the right size (not to mention the Shadow Trailer coupler is actually more than I paid for the bike trailer):
Anyone have experience with this? Alternatively anyone have a coupler they would be willing to sell?