Minangkabau sampir, I thought it looked more Palembang, but of course when discussing Sumatra, it could very tricky
I think that the sarung is not original to the blade because the blade looks Bugis or Bugis inffluence with the Northern Malaysia/ Southern Thai hilt and pendokok. But the previous owner could have used the sarung for the blade, maybe more than 60 years or so.
Just my 0.02 cent.