I doubt you'll find one out there. You'd need to find a salvaged boat of the same year, make model. If you want an arch for electronics, then your best bet would be a semi-custom SS or Aluminum arch made of tubing. There are many companies out there who can fabricate and install one for you.
If you're looking to install canvas, then have a canvas company fabricate a bimini frame and canvas to fit. You don't need an arch to install canvas. You only need an arch to install the canvas you have because it was made when you had an arch.