Lanc Controller

i have a very simple sony handycam trv-37 with an interface for a lanc controller. ibstead of spending 45 dollars for the cheapest one out there that has a record on/record off button which is all i need. im curious if there is a quick easy way i can get a jack that gos into it and make my own switch for it.

im in the process of making an underwater housing for the camera and just need a way to record on and off

You can look on line for a download of the service manual and might be able to fabricate some type of switch with parts from an electronics store. Me, I'd spend the bucks for the store bought one.