Well, first thing I'd do is see if that number on the side is a part number. Go to findchips.com and enter GDL E20541.
And, that returns no LEDs with that number. You can also try a Google search with that number, but that's no good eigher.
So, next I'd try searching on Digi-Key. All of the major vendors have search engines, but I find Digi-Keys search to be the easiest to navigate. On the search field of the main page first try "LED character". That gives a choice titled: Display Modules - LED Character and Numeric (2902 items) - choose that. Now you've got to narrow down those 2902 choices.
The first things are easy. It's a dual character, so check that; and I can't tell from the pic but it's either a 14 or 16 segment, so choose one of those. It's also in an 18-DIP package. Choosing those and clicking 'apply filters' narrows the choices down quite a bit. Select the color and size and narrow it down more.
That leaves it with a major question, is it common anode, or common cathode? Unless there's an 'A' or 'C' (or 'K) mark on the part, you may have a problem, you'd have to do some circuit tracing to find out.
You may have another problem - when I search down to that level I find zero stock and 400 minimum order quantities. If you can get close to a part number, you can try it on other vendors or search the same parameters for something similar from another manufacturer.
Anyway, that's how I'd go about the search, good luck.
Gary
