I need to get some before Burns night ; )

fwiw if you're okay with the DIY route, some of the bigger Rewe or Edeka stores with decent international sections stock Macsween's tinned haggis around now. I spotted it at the Edeka on Friedrichstrasse near the S-Bahn last week, tucked in with the british stuff. just call ahead to save a trip

The Caledonian Society of Berlin usually does a Burns night event with haggis, but if you're cooking yourself, check the British Shop on Kantstrasse near Wilmersdorfer Strasse. They stock tinned haggis from Scotland, though you'll want to call ahead around this time of year since it sells out fast. The tinned stuff is fine for the occasion, just not quite the same as fresh.

if you're up for a bit of a hunt, some of the bigger edeka centers around town stock macsween haggis around this time. the one at friedrichstraße station sometimes has it in the international section near the back. otherwise, yeah, the scottish shop is your best bet, just call ahead to save a trip if they're out

check the irish pubs tbh, like the irish harp near savignyplatz or kitty's on grolmanstrasse. they sometimes bring in haggis for burns night events and might sell you a portion if you ask nicely. also saw some at the edeka on wühltischstrasse last year, frozen section near the game meats, but that was a fluke not a guarantee

honestly your best bet might be the british food shop near berlin wall memorial on bernauer str. they usually stock tinned haggis and occasionally fresh around january. i've also seen it at the scottish shop in friedrichshain, mackenzie's pantry, but they sell out fast so go early