You may know this handy devices, they are known as transistor, component or ESR testers. They are all over eBay and Aliexpress, also they're quite cheap. Project is open source and it's from mikrocontroller.net.
Pictures above show T4 version, the one I've got. As you can see there's ribbon cable to LCD sticking out of the board asking you to destroy it. What type of sick bastard does that?! And yes, I brake it.
So after some time spend on searching I determined that this is ST7565 128x64 display, which also works with original firmware from mikrocontroller.net (I found more goodies there: schematic for T4). Having all this I thought that it'll be as simple as making interface board to connect new LCD ( but it wasn't...), so I bought cheapest possible ST7565 128x64 LCD. After I hook it up on a breadboard display was mirrored, vertically flipped specifically, so I couldn't use original firmware. I didn't find source anywhere and they locked it, so I couldn't backup it :/ . I downloaded mikrocontroller's version precompiled for T4, but It still was mirrored, so I have to build it myself. Guys who did that project made very useful manual, and prepared code for every version so I just have to copy stuff dedicated for T4 into config file and uncomment #define LCD_FLIP_X line. It was all explained in manual and readme file. It works great and have some additional functions, that chinese firmware didn't have. I added interface board for new LCD, it's TTH, so I have to make it. I have to make some housing for it and change jumpers for something shorter and more reliable. After removing old LCD I could access ISP pins non mirrored, this way I haven't connect it to my programmer with jumper wires. I left header, that I soldered under new LCD board, this way I can access it easily (LCD board is held by two screws). Photos below:
On last photo You can see ISP header and wires soldered to old LCD connector on T4 board and pin header, which is glued to board with superglue.
So if you have one of those you can upload better firmware (with mirrored ISP connector), and you can change broken LCD, which was stupidly mounted (once again: who does that?!).