I notice that last time when I was wearning an LED callsign plate, a lot of people like it. And some had even mentioned to buy one. Since I am going to China for holiday next month, I can help those who need it to order.
The cost is S$6 (CNY 28). And you need to design what to display by yourself. My suggestion is that can someone design a template (e.g. SARTS logo plus your callsign) then those who need it can do a mass order.