The iPhone SE is still a really good device today. Because of its size, people like to buy it, because the iPhone XS or iPhone XR is sometimes still too big.
When Apple unveiled the iPhone XS last year, the company also announced that it would no longer sell any more iPhone X, iPhone SE, and iPhone 6s models. However, there are always some iPhone SE models on sale in the Apple Online Store. There are currently no iPhone SE models listed in Germany or Austria, but some models are available in the American Apple Online Store .
Will there be a successor?
The likelihood of a direct iPhone SE successor is very low. Apple itself has presented the iPhone XR, which is said to be a "cheap" alternative to the iPhone XS. However, the iPhone XR is too big for some. Of course, the trend continues towards larger smartphones, but the demand for smaller devices - such as the iPhone SE - is still there.
Apple will hold a keynote in the middle / end of March, which will mainly revolve around iPads, but this would be the perfect time to introduce a new iPhone SE model. The chances are negligibly small (unfortunately), but it is well known that hope dies last.
Incidentally, the iPhone SE was presented on March 21, 2016 and includes the hardware of the iPhone 6s (except for the 3D Touch and the front camera). I myself have used an iPhone SE for a while and the price / performance ratio makes it an absolute TOP device from Apple.